Beginners Guide to the Vintage Macintosh
This will be a simple guide with tips on how to work with vintage Macintosh computers. The focus of this guide will be Macintosh models of the 1980s and 1990s.
- 1 Getting Started
- 1.1 Which Macintosh Is For Me?
- 1.1.1 68k or PowerPC?
- 1.1.2 Laptop, Desktop or AIO?
- 1.1.3 Models In High Demand
- 1.1.4 Other Model Considerations
- 1.1.5 Do I Need A Hard Disk?
- 1.1.6 The 32-bit Clean Macintosh
- 1.1.7 Do I Need A "Tweener" Mac?
- 1.1.8 Clones & Other Oddities
- 1.2 Buying A Vintage Macintosh
- 1.1 Which Macintosh Is For Me?
- 2 Using A Vintage Macintosh
- 3 Upgrading A Vintage Macintosh
- 4 Troubleshooting
- 5 See Also
This section will cover the basics on types of Macintosh models and where you can frequently find them.
Which Macintosh Is For Me?
From my own personal experience, I decided to get into Macintosh models I either used or really wanted when I was younger. We'll take a look at some considerations to help you decide which vintage Macintosh you may want to look for.
68k or PowerPC?
There was a major shift in the Macintosh architecture right around 1994 as the release of the "Power Macintosh" models replaced the Motorola 680x0 based CPUs with the PowerPC processor. The Power Macintosh models will generally run most 68k applications, but there are some things to consider.
- Early Power Macintosh models may run 68k applications slower than the actual 68k systems. For example, a 68k-only application may run slower on a Power Macintosh 6100 than a Macintosh Quadra 840av despite the PowerPC being the faster CPU. 68k software runs in behind-the-scenes emulation on PowerPC.
- Some very early 68k software such as games for the original black and white compact Macs may not run properly on later systems.
- System 6 or earlier will require an older 68k. Mac OS 8 will technically run on a Motorola 68040 but is better suited for PowerPC. Mac OS 8.5 and up will only run on a PowerPC.
- System 7.5.5 is a good stable system and should run on any 68k Macintosh, but systems under 4mb RAM should consider 7.1 or earlier.
- System 7.1.2 is the first to support PowerPC and can be run on the early Power Macintosh 6100/7100/8100 models.
Laptop, Desktop or AIO?
Factors such as your planned usage, available desk space, ability to perform electrical repairs may influence the choice of vintage Macintosh you should be looking for.
- The PowerBook Duo line of sub-notebooks do not include a floppy or CD drive. Without a Duo Dock or mini dock setup, you'll need network connectivity with another Macintosh via serial port to transfer files over.
- The LCDs in the earlier PowerBooks have capacitors which fail due to age and will require replacement. These will cause issues with the display as they fail.
- In some models such as the Macintosh PowerBook 3400c there is an internal PRAM battery which is known for leaking and damaging internal components over time.
- Early PowerBook Duo models seem to have a poor quality keyboard prone to mushy key feeling or keys not working at all. A thorough cleaning may help.
- Passive-matrix LCDs probably won't be suitable for gaming.
- Some models of power supplies are more prone to failure from age and may require repair.
- Memory upgrade modules, in particular the modules offering the highest capacity available, tend to be harder to find for some models. This will lead to higher prices on the used market.
- You'll use up more desk space than a laptop but you'll likely have more expansion options.
- Nearly all desktop vintage Macs will require logic board recapping. The power supplies in the LC line also seem more prone to failure from age.
- Able to use consumer VGA LCDs with adapter instead of a bulky CRT.
- Like the desktop models, you'll most likely need to recap the logic board. This will also apply to the analog board driving the CRT.
- Typically a fixed screen resolution.
- Certain models used cheaper shadow mask CRTs (LC 580, Performa 5000 series models). Trinitron is better.
Models In High Demand
There's a number of Macintosh models which are far more expensive than others on the used market. Some of these are desirable from the performance standpoint while others are more collectible due to rarity.
- Macintosh Quadra 700 - Mid-range performance as a Motorola 68040 based Mac but it uses a mini-tower form factor, while most Macs at the time were designed to sit under the monitor as a desktop. The Quadra 700 also made an appearance in the Jurassic Park film, adding to its popularity. An additional benefit of the Quadra 700 is the lack of the commonly used SMD electrolytic capacitors which leak over time and require replacement.
- Macintosh Quadra 840av - Fastest production Motorola 68040 Macintosh as it clocks in at 40MHz. The tower design is visually appealing but it is not known for being pleasant to work on. The interior plastic components are also prone to breaking if not handled carefully, making shipping these units risky. The "AV" component of this system is also something not found in most Macs, but not a whole lot of software took advantage of this.
- Macintosh Quadra 950 - Not as powerful as the 840av but the Quadra 950 is the ultimate server tower from the Motorola 68040 line. This tower features six NuBus slots and room for various other expansion options. The Quadra 950 is the best choice for Apple UNIX (A/UX) hobbyists.
- Macintosh TV - This system is not overly powerful, but it is a fairly unique Macintosh due to the all-black design. The short production run on this model also makes it harder to find these days.
- Macintosh SE/30 - The SE/30 is the top of the line for the black and white compact Macs. The internal expansion port gives you a number of options, even doing multiple cards at the same time with the use of angled adapters and the like. This system can even hold 128MB RAM. This system can also run Apple UNIX (A/UX).
- Macintosh Color Classic - In stock form these compacts aren't overly powerful, and they top out at 10MB RAM. Another problem is the screen resolution making it incompatible with some games. These are likely more popular in the "mystic" upgraded form which is the use of an LC 575 logic board, and often implementing a hardware hack allowing the CRT to display 640x480 resolution.
- Macintosh LC 575 - This model is the most powerful of the 68k all-in-one Macs and uses a much nicer display than the LC 580 which was the last of the 500 series. These are probably going to be harder to find intact due to the popularity of taking the LC 575 logic board and using it in a Color Classic.
- Macintosh 128K - Carries value from being the first model of Macintosh, but also due to rarity as many owners of original 128K systems likely performed logic board upgrades to the 512K. Original 128K boards were taken back by the vendor, reducing the number of actual original 128K systems in use.
- Macintosh PowerBook 2400c - This is a sub-notebook design like the Macintosh PowerBook Duo 2300c but seems to have been more popular in markets outside of North America, making these harder to find.
- Macintosh IIfx - This was the most powerful Macintosh using the Motorola 68030 processor and also used some other unique internal components. These were very expensive at the time and still carry value in the used market from being the most powerful Macintosh II but also being harder to find.
- Macintosh Portable - Not a very practical Macintosh to actually use, but these take some effort to keep in running condition so working units are becoming harder to find.
- Twentieth Anniversary Macintosh - The TAM design makes it a unique vintage Mac, but the original price kept it from selling in high volume making it a rare computer these days. Expect to pay a large amount of money if you really want one of these.
Other Model Considerations
- If you're looking into a 6200/6300 series Performa, the recommended model for best performance is the 6360 as this is PCI-based instead of NuBus like the earlier models.
- Despite having a 32MHz CPU, the Macintosh IIvx is said to actually be slower than a Macintosh IIci due to a 16MHz bus speed.
- The PowerPC 601 chip on models such as the Power Macintosh 6100 is very fragile and can easily break if too much force is applied to the heatsink. Due to age, the processors may also overheat and die if the heatsink compound is not replaced (also applies to Power Macintosh 7100).
- If you're looking for a Macintosh capable of running Apple UNIX (A/UX), the system must be equipped with a PMMU, FPU and not be an AV model. No LC models are compatible. No PowerPC model will run A/UX.
- Early compact Macs which don't have an internal fan for cooling (128K/512K/Plus) may overheat if used for long periods of time. A third party "system saver" fan device is a recommended accessory.
- The Macintosh PowerBook 5300 is not a very desirable model as the lack of L2 cache causes performance to suffer. You also cannot use a CD-ROM drive in the hot swap bay.
- The logic boards of the 128K/512K/Plus/SE models do not use the capacitors known for leaking, though the analog boards may still require repair.
Do I Need A Hard Disk?
For those of you looking to get into an early compact Macintosh such as a 128K/512K/Plus, these models did not offer factory internal hard disks. The Macintosh Plus and all models after it provide external SCSI for hard disk support, but do you actually need one? On a vintage Mac with no hard disk and a single floppy disk drive, you must either fit all your applications and documents onto the same disk as your system software or you will need to swap disks (often numerous times) when you decide to run other applications. You are able to eject the system disk from the Macintosh and still keep the computer running, but it will prompt you for the disk any time it needs to load system data. To make your life easier, there are some options:
- Find a second floppy disk drive. This was a more common solution for 128K/512K users as these Macs did feature a port for adding another floppy disk drive. This means you can keep your system disk in one drive at all times. Some models such as the Macintosh SE and Macintosh LC were available from the factory with two floppy disk drives.
- Use a RAM disk for your system folder. It is possible to boot your Mac off a floppy disk which then creates a temporary system drive out of available RAM. This removes the need for keeping the system disk in the drive, but as it uses system RAM this will likely not be a viable option unless you have more than 1MB memory.
- Use the BMOW Floppy Emu. This is a modern accessory for vintage Macintosh hobbyists which connects an SD card into the Macintosh floppy disk port. This is an alternative for systems which did not come with SCSI, but this product can also be used on any vintage Macintosh with a floppy disk interface.
- Use ROM booting. While the Macintosh Classic is the only Macintosh to actually offer ROM booting, systems with a ROM socket can use a product called the ROM-inator II. These include a small System 7.1 folder among other benefits such as making the Macintosh 32-bit clean. This is more of a "for fun" gimmick as you can't make changes to the system folder.
The 32-bit Clean Macintosh
What does this mean? The early Macintosh CPUs were 32-bit but used 24 physical address lines which limited the amount of memory which could be addressed by the system. This began to cause problems for systems which could physically hold more than 8MB RAM, but the operating system wouldn't properly address this space. The System 6 software cannot deal with memory amounts greater than 8MB, but System 7 would ship as being 32-bit clean. Unfortunately there were still "dirty" ROMs which still did 24-bit addressing during the boot process, requiring a third party utility called MODE32 to force 32-bit addressing during boot. Macintosh models prior to the IIci are generally known as being "32-bit dirty" models. If you intend on running Mac OS 7.6, you will need a 32-bit clean Macintosh.
Do I Need A "Tweener" Mac?
If you don't already own a vintage Macintosh computer, you may want to consider a model which offers some modern conveniences such as Ethernet plus a CD-ROM drive and a floppy disk drive. This sort of vintage Macintosh can help act as a bridge for working with much older systems. For example, only another Macintosh computer can write to the 800kb double-density floppy disks used in earlier compact Macs. Apple used a sort of variable speed design which is not compatible with PC drives, so you'd need to already have the proper software disks to use an early compact Macintosh as your only vintage Macintosh.
Vintage Macintosh models with high-density floppy drives and are running System 7.x with PC Exchange can read DOS formatted disks. You won't find floppy drives on modern PCs but a USB floppy drive will work for transferring files. Zip drives were also popular for transferring data between systems and a few different Macintosh models such as the Power Macintosh 6500 and Power Macintosh G3 included this option at the factory. Zip drives could also be found on PCs either externally via parallel port and USB, or internally with IDE.
Clones & Other Oddities
A short lived business decision by Apple in the 1990s opened the Macintosh market to third-party clones. These are harder to find now and as such can be desirable collectible systems for hobbyists due to the rarity. If you come across these clones from vendors such as Radius, Power Computing, Motorola and UMAX for a reasonable price it might be a wise investment.
The Apple Network Server (ANS) product is an interesting system for hobbyists looking for a unique Apple system which can't run the Mac OS, as they were only designed to run IBM's AIX. These are also hard to find as the large size makes them less ideal for storage or display in vintage collections. We believe many of these systems were either returned to Apple or recycled over the years.
Buying A Vintage Macintosh
Things You Need To Know
- Most Macintosh models from the 1980s and 1990s will require logic board work due to leaking electrolyte from SMD capacitors. If this work has not been done, the system may still work but slowly die as electrolyte comes in contact with logic board components. If you are not capable of doing this repair work yourself, you should factor this work in to your purchase budget.
- The original PRAM batteries are notorious for leaking onto the logic board and in some cases completely destroying the board. If you're purchasing an "untested" Macintosh without being able to see the inside of the unit, be warned that you may end up with irreparable damage to the board. Most Macs will function without the battery but for units which require one, make sure you buy a brand new one with a recent manufacturing date and not one sitting on a shelf for 10 years.
- The so-called "Spindler plastics" (term used by hobbyists to describe the brittle case plastic likely from cost cutting under CEO Michael Spindler) in a number of 1990s Macintosh models can sometimes result in units destroyed in shipping due to insufficient packaging. Unfortunately even with the most careful packaging, you may still encounter damage due to the age of the plastics. If you absolutely must buy a 1990s Macintosh with shipping involved, make sure the seller packs the unit very well.
- The original hard disks in older Macintosh computers may still work but will generally have horrible bearing noise. SCSI hard disks in good running condition are hard to find now, and with age they will only get worse. Don't spend too much time trying to find a working hard disk unless you really want the vintage sound of spinning disk. Options such as the SCSI2SD are far easier to deal with. For IDE models, solutions such as IDE to Compact Flash or IDE to SATA should help.
Where To Find Macs
- eBay - While online auction sites such as eBay will give you the best selection, eBay sellers are known for inflated prices far beyond actual market value. Impulse buying on eBay may cost you more than a system is worth, and you should instead spend some time researching previous sold prices to get an idea of the going rate. You may still find used Macs for cheaper elsewhere depending on your geographical region.
- Flea markets - You might be able to get some great deals at a flea market, or you might find nothing at all.
- Local classifieds - Craigslist/Kijiji/etc are often good places to find used Macs, assuming you live somewhere with decent population. Prices may vary from great deals to worse than eBay.
- Recyclers - Organizations that do scrap recycling may receive vintage Macs from people who don't know any better, but not all recyclers will let you walk in and take/purchase computers that have been dropped off. If the recycler doesn't already do reselling, you'll probably have to make friends with someone working there.
- Surplus auctions - You're probably not likely to find any real old Macs in government/education surplus auctions, but worth checking out if you're looking for G4 era Macs.
- Estate sales - Might be a good place to start if you're hoping to find forgotten Macs from someone's attic.
- Thrift stores - Some thrift stores may not sell computers and instead send them directly to recycling, but it's probably worth going to stores such as Goodwill or Value Village.
- Vintage Mac communities - A great place to buy and sell vintage Macintosh systems is the forum at 68kmla.org. Other sites to check include Applefritter and VCFED. As of 2019 there are also numerous Discord servers dedicated to vintage computing and you may find other people to conduct deals with.
Bought A Vintage Mac... Now What?
Here's a quick checklist of things you may want to do to help get you set up with a vintage Macintosh.
- Clean and re-cap the logic board. If you don't care about keeping the exact factory look, tantalum capacitors make good replacements for the original SMDs.
- If you're using an all-in-one Macintosh or a separate Apple CRT, inspect the analog board for bulging/leaking capacitors and replace if necessary. This is especially important if you notice "glitches" in the display as this tends to be an indication of failing components.
- Clean the floppy disk drive. The older auto-inject disk drives tend to get dirty easily and cause issues with reading disks. A good cleaning may help with this.
- Replace the hard disk if the mechanism is overly loud or if you encounter data corruption. The SCSI2SD is a popular choice for hobbyists.
- Retr0bright the case if the original color has since been replaced with a brown color from UV damage. If you like to display your vintage Mac collection, having them back at the original color is probably appealing.
Using A Vintage Macintosh
Once you have your hardware up and running, you'll probably want to get your operating system set up and some applications or games loaded.
Vintage Macintosh software can be obtained from a number of online sources. You may also find software available on protocols old enough to be directly compatible with your Macintosh system, assuming it has Internet access. Most modern websites will not render on old Macintosh web browsers, so you may need to download software on a modern computer and then transfer it to the Macintosh afterward.
- http://68k.preterhuman.net - A small collection of 68k-compatible Macintosh software. This site should render in Macintosh browsers as far back as Netscape Navigator 2.x.
- https://preterhuman.net/software/ - Software downloads which may be a mix of 68k and PowerPC.
- https://winworldpc.com - Most Macintosh operating systems can be found here, with a moderate collection of applications/games available.
- https://macintoshgarden.org/ - Large collection of any and all vintage Macintosh software.
- https://www.macintoshrepository.org/ - Similar selection as Macintosh Garden.
- http://www.powerpcsoftware.com/ - Later PowerPC software (G3 and up).
- http://www.oldapps.com/mac - Useful archive of different versions of software.
- https://archive.org/details/software - The Internet Archive is a vast collection of everything. Mostly CD images are found here.
- https://www.vintageapple.org/macdrivers/ - Good collection of Macintosh driver software for various components and accessories.
- https://preterhuman.net/drivers/ - Some misc Macintosh driver software.
- ftp://ftp.atlas.altexxa.net/software/mac/ - Smaller collection of the content available on the preterhuman.net Hotline server.
- hl.preterhuman.net - This is the Hotline/KDX server run by preterhuman.net and features a large collection of vintage Macintosh software.
As Macintosh applications use both a resource fork and separate data fork, they must be compressed before being stored on filesystems which do not support this (such as DOS/Windows). This unfortunately causes a problem when it comes to extracting archives as you need to already have a copy of a decompression utility such as StuffIt Expander, but this wasn't always included with the base Macintosh system software. You can typically find these types of utilities bundled in with copies of Mac OS 8 and up, or on the demo/shareware CDs you'd find in Macworld/MacAddict magazines. For accessing downloaded software, here are some utilities you'll probably need:
- StuffIt Expander version 5.5 or later - There was a change in the StuffIt format in version 5.5 so any archive made with version 5.5 or later will require Expander version 5.5.
- DiskCopy version 6.x - This is to mount disk images. The earlier version 4.x may not read newer images so finding the latest 6.x copy is recommended for compatibility.
- Adaptec/Roxio Toast - The Toast format is probably the most popular for Macintosh CD images, and the Toast software will mount and burn CD images (assuming you have a CD recorder).
- ShrinkWrap - This is a disk image utility which may be handy if DiskCopy is not working with a particular image.
If you intend on using Apple's System 7 operating system, this was available both on high-density floppy disks and CD-ROM. Any Macintosh with an integrated CD-ROM drive should be capable of booting off the system software CD, and most desktop Macs should be capable of doing the same with an external Apple CD-ROM drive.
- CD images of System 7.x versions found online may be in Toast format, typically requiring a Macintosh with a CD recorder to properly burn. Some online download repositories may have the CD image available in ISO format, which should work with being written to CD on Windows or Linux workstations.
- Floppy disk images and be obtained online but will generally require a Macintosh to properly write to floppy disk.
- Actual Apple install disks can often be found on sites such as eBay. You may also find third parties offering to write the install images to blank disks for less cost.
- If you're using a SCSI2SD as a hard disk, you can potentially raw write a complete Macintosh disk image to your SD card with everything already included. You'd need to find someone to provide this sort of thing.
- Early versions of System 7 will have a 2GB partition limit on HFS. On larger disks you can either have multiple partitions or use a third-party utility such as FWB Hard Disk Toolkit to install a custom driver capable of larger volumes.
- If you plan on running Mac OS 8.1 or newer, you should use the HFS+ filesystem as it offers some advancements over HFS. Note that this will require a fresh format, and no OS prior to 8.1 will be able to read it.
You may encounter applications which specify either 68k or PPC (PowerPC). 68k applications will run on a PowerPC though slower due to the required emulation, but PowerPC applications will not run on a 68k processor. Software applications were also commonly distributed as "FAT" binaries which included both the 68k and PPC code at the expense of larger file size.
- If the disk image file extension is ".dmg" this is for Mac OS X based computers, not classic Mac OS.
- If you have a disk image which DiskCopy will not read, the file's owner and type codes may not be correct. This may happen to files copied from other platforms without being compressed inside a .bin/.sit/.hqx container. ResEdit can be used to set these attributes (match them with a working disk image file).
Tips & Tricks
- Command + Option + P + R (during boot) - This will wipe the PRAM contents. If you're experiencing strange issues with your Macintosh or problems like video not being displayed, clearing the PRAM may help.
- Command + Shift + 3 - Takes a screenshot in PICT format and places it in the root of your hard drive.
Upgrading A Vintage Macintosh
While your Mac may function just fine in stock factory form, there are numerous ways to improve the performance or usability. Certain upgrades may have come with high cost back when these systems were new but can be found for very cheap these days. Other upgrades may have become even harder to find, with one of the most expensive third-party upgrades being the Micron Xceed Color 30.
Understanding Internal Expansion
The first vintage Macintosh to offer internal expansion is the Macintosh SE, but earlier models did have third-party upgrades available via direct board attachments (not really factory supported). To expand the Macintosh SE, you want to find "SE PDS" cards. This is also different from "SE/30 PDS" as the cards sit at a much different angle inside the case. The Macintosh IIsi also shares the same PDS as the SE/30, but it is important to note that some SE/30 cards may not work in the IIsi due to the bus speed difference (16MHz vs. 20MHz). Yet another type of PDS is the LC PDS found in the LC models, and even these have differences between them as the slot size was extended in the Macintosh LC III likely from the new 32-bit bus. Existing LC PDS cards will still work fine, but PDS cards specifically for the LC III and up will not work in the LC or LC II.
NuBus was more of the "standard" method of expansion starting with the Macintosh II and continuing up until the first Power Macintosh systems prior to the switch to PCI. Most of the Macintosh II line offered direct NuBus expansion, though in the case of the Macintosh IIsi you needed to use an adapter. You could typically find any type of expansion available for NuBus such as networking, video cards, sound cards, PC compatibility, specialized industrial applications, etc.
PCI came along in the Power Macintosh models such as the 7200/7500/7600, 8500/8600, 9500/9600. Some types of PCI cards such as video cards require a special Macintosh compatible firmware in order to work, but any Ethernet cards should work assuming the vendor released a Macintosh driver for it.
There are some "custom" types of expansion slots found in a few different vintage Macintosh models. In the Macintosh IIci, a cache slot was available for a 32kb cache upgrade available from Apple. Third party vendors also released CPU accelerators for this slot. In the Macintosh Quadra 700, an "040 PDS" option allowed for Power Macintosh upgrade cards. The first Power Macintosh models also offered a type of PDS in addition to being NuBus based, though in the 6100 you could only physically fit one card so it was either PDS or NuBus. In the 7100 and 8100, PDS was generally used for the video card.
See our page List of expansion cards for Macintosh for an idea of available expansion options.
Most Common Upgrades
It costs far less money these days to bring your vintage Macintosh to the maximum RAM capacity (may not fully apply to systems with rare memory such as the Macintosh IIfx). Memory upgrades at one point may have cost you hundreds or thousands of dollars, but now it may cost you $20-50 for enough RAM to completely fill the system. eBay seems like a safe bet for buying RAM upgrades for your Mac, and some eBay sellers will even specify which vintage Mac models the RAM is compatible with. Make sure you're aware of memory speed, FPM, parity, voltage requirements. 30-pin and 72-pin is fairly straightforward but there are some models such as the Power Macintosh 4400 which use 168-pin 3.3V EDO DIMMs. These aren't the same as 168-pin SDRAM which is far more common.
Home users in the 1980s and 1990s were more likely to use a modem instead of Ethernet in the home, but these days having your vintage Mac on a home network makes it easier to download software. As many vintage Mac models either featured no internal expansion or only one expansion slot, getting Ethernet on your Mac may limit your other expansion options.
- For LC models, the LC PDS Ethernet card is fairly easy to find and shouldn't be too expensive. You may also want to find a card with a math co-processor socket as you can find cheap Motorola FPUs online.
- For models which offer the Apple Comm Slot on the board, finding a compatible Ethernet card for this slot will keep your primary NuBus/PDS/PCI expansion available for other upgrades.
- For models without an available expansion slot, there are external options such as a SCSI to Ethernet adapter or the AsanteTalk which bridges the Apple serial port to Ethernet.
- Models with the AAUI port just require a transceiver to connect to 10BaseT, and these are typically easy to find.
One thing to keep in mind on modern networks is compatibility with 10Mbit network adapters as most Ethernet solutions prior to PCI will be 10Mbit only, not 10/100Mbit. Some newer network switches may no longer negotiate Ethernet at 10Mbit.
On systems with limited expansion slots, upgrading the onboard Apple video memory might be a better option than using a separate video card. VRAM expansion can be done on a number of the LC and Quadra/Centris models. Performing this upgrade is mostly just replacing stock 256kb VRAM SIMMs with 512kb SIMMs. This upgrade will let your display support more colors at higher resolutions. 512kb VRAM SIMMs are still available on the used market but will be a bit harder to find these days.
The HPV display cards for the PowerPC PDS also feature expandable VRAM.
Depending on what you hope to get out of your vintage Macintosh experience, you might like to find an older chassis and perform a CPU upgrade allowing you to run newer software. The used market for CPU upgrades varies quite a bit and you may be looking at $200+ for the rarer upgrades. In systems with limited expansion such as LC models, you'll also lose the ability to use other important internal upgrades such as Ethernet. Most of the PCI based Power Macintosh systems used CPU daughtercards giving you very easy upgrade options. Other upgrades were even available for the L2 cache slot on fixed-CPU systems.
For hobbyists experienced with electronics repair, performing overclock on the logic board by replacing the crystal oscillator with one running on a higher frequency is an option but you may not want to lose the "authentic" feel of the hardware. This may also cause incompatibilities with other components such as internal video or the serial ports.
For some systems, adding a math co-processor is a simple upgrade but not something you may ever really need to do. These would have cost more significant money back when these systems were released, but now you can find Motorola MC68881/MC68882 co-processors on the used market for a few dollars. If you've got a vintage 68k Macintosh with an FPU socket, might as well drop one in. For LC/Centris 040 systems, you can add FPU support by replacing the original Motorola 68LC040 CPU with the full Motorola 68040.
This section will cover brief troubleshooting information for vintage Macintosh hardware and software. For more detailed information specific to certain models, please visit our Apple Computer article and find your model in the product list.
Mac chimes but there is no video signal
Models such as the Macintosh LC 475, Power Macintosh 6100 along with a few others will require a working PRAM battery installed or the system will not boot. Research your exact model to determine if this requirement affects you. Other causes may include a screen resolution incompatibility or failing capacitors on the logic board.
Mac freezes or produces a bomb crash during boot
This often means the OS is attempting to load an extension or control panel which is either conflicting with another piece of software or is incompatible with your hardware in general. If you reboot the computer and hold down the shift key right away (before the "happy Mac") until you see the extensions disabled message, it should allow you to boot and disable the problematic software. If the boot still fails, you may have a corrupted system file or a failing hardware component.