Since I received one the first CarrierZIF cards, I did not get a printed manual, only an Adobe Acrobat PDF file version on CD. Normally retail XLR8 cards come with a well illustrated manual with photos of the installation steps required to install the card in 73/75/7600, 85/8600, 95/9600, and a text only overview of UMax/PowerComputing installations. (A complete list of compatible models is shown on the front page and specs page of this review.) The PDF file is a mirror of the printed version I assume. The manual also has sections on tools required, explanations of CPU and cache speeds, software installation and a step-by-step guide to troubleshooting. XLR8's toll-free tech support number is also listed in case you have questions or need assistance. XLR8 also supplies a permanent (vs. the disposable one time use version) adjustable anti-static wrist strap which I recommend you use. Often you may not destroy an electronic component from static discharge, but you shorten its life which can lead to sudden failures down the road.

Although a better way to get a feel for the installation is to download a sample manual (MAChspeed for example), a summary of the normal installation routine would be:

[Note: As noted in my original First Look at the CarrierZIF article, for PowerComputing PowerCenter owners with the plastic CPU Fan bracket, I suggest you trim the two topside protruding tips of the plastic bracket back about 1/8" with a pair of scissors so the bracket slides back in place easily. This does not affect support as the bracket U channel that holds the card edge remains intact. Take a look at this modified bracket photo. It took 10 seconds to trim the tips back. My PowerTower Pro 180 has a metal bracket and did not need trimming.

1. Install the XLR8 Software (do this first, especially if you own an Adaptec wide SCSI PCI Card as noted in the XLR8 2940UW Tech Note)
2. Shut Down the Mac (disconnect the AC power cord to prevent accidental powerups should you inadvertently press the keyboard power-on key, etc.)
3. Attach the wrist strap and connect it to the monitor out jack on the back of the Macintosh.
4. Remove the case cover
5. Remove the existing CPU card from its slot
6. If possible - remove the L2 cache dimm. Most G3 upgrade problems are due to too slow an L2 cache. with the G3 card's fast backside cache you don't need it and especially with Apple's stock cache dimms - most will be a source of problems.
7. Verify that the CarrierZIF speed settings are correct (manual has table of settings)
8. Insert the CarrierZIF card (making sure it's fully seated)
9. Press the CUDA (cpu reset) button on the motherboard (hold for 30 seconds)
   (Note: I often don't do this - at least with machines with a IXMicro or Thunder3D graphics card installed since with these cards Zapping the PRAM or resetting the CUDA switch results in no video at boot until you remove the card, power up the mac, shut down and then reinstall the card.)
10. Replace the Case Cover
11. power up the Mac.

Total installation time was under 5 minutes, but if you want to experiment with faster than rated speeds you will need to adjust settings and then verify that the new speeds are reliable (I'd suggest at least 12 hours of heavy apps use to verify reliability). Should your system not boot follow the steps in the troubleshooting section of the manual and some tips are also noted below.

The card has a removable black metal bracket that allows it to be used in low profile systems like the PowerComputing machines (the bracket is left on for use in Apple Macs). Below is a picture of the card installed in the Genesis (NOTE: The picture shows an aftermarket Pentium Fan/Heatsink I added after the review tests - the standard heatsink supplied is a flat plate).

Speed Settings:

As mentioned earlier, the CarrierZIF card has adjustments for 40 to 60MHz Bus speeds and up to 8X Bus to CPU ratios (future G3 CPUs are rumored to have 10X ratios which would have allowed up to 600MHz CPU speeds with a 60Mhz Bus speed).

Important Note: Along with the benefits of a wide range of adjustments comes some responsibility. This card allows setting bus and CPU speeds to rates beyond the rating of the CPU and possibly your system's capability. You need to consider the installed ZIF module's rating and the limits of your particular Mac (don't start out with high settings that have not been proven reliable in your system/CPU module combination). Here is a basic guide I follow when experimenting with speed settings in my Macs:

1. Before any major upgrade, especially when experimenting, back up your data just in case.
2. As a starting point, I set the card to a low bus speed (45MHz or less if I don't know the machine history). If it has a 400MHz ZIF module I set the bus speed to 50MHz and ratio to 8 since that is a must to run 400MHz [50 x 8 = 400])
3. I double check that the ratio setting is correct (set to so that bus speed times ratio does not exceed the CPU speed). Don't rush, take the time to verify that the settings are correct per the manual. It is important to not overclock the CPU or cache during the process of finding a reliable bus speed - you want to isolate one factor for reliability, not confuse the issue by running the CPU or cache beyond its rated speed.
4. If the system does not boot at the current bus speed setting and I've made sure the card is fully seated, and I have removed the L2 Cache dimm (if possible - some systems have soldered-in cache, so deinterleaving RAM or lowering the bus speed are other options) then lowering the bus speed may be the only option (after verifying your CPU/Bus ratio setting is within CPU's rated speed limits).
5. Once the system boots, I verify reliability by running applications that stress the CPU for hours to make sure the card is reliable. Simply booting and running MacBench is not proof. If you own Unreal or Quake, letting the auto-play demos run for hours is a great way to test for problems.
6. As a test for hard driver data errors - try mounting an Apple SMI file image which will do a checksum test.

Warning/Disclaimer: Overclocking may void the warranty and may not be reliable at all speeds. I do not recommend overclocking to others and you assume all risk from doing so, although as noted in my Rate Your G3 Upgrade database most everyone seems to be doing it. Check with XLR8 on their current warranty policy if you plan on overclocking the card and are worried about warranty support. No company can guarantee overclocked speeds or what bus speed will be possible in your system.

With the XLR8 400Mhz ZIF module installed I ran the found the following settings reliable on my Macs which contain good quality RAM in matched pairs.

Update: Read my Illustrated CarrierZIF Setup Guide for more info on the card's features, speed settings and important info on using other brands of ZIF CPU modules.

This is only for reference, not a guarantee you can repeat these results or an encouragement for you to overclock your card but here are the Fmax (Max Freq) settings I tested in this particular sample in my systems:

1. Genesis: (9500 motherboard: 50/55Mhz bus speeds (interleaved RAM)
2. 9600/350: 50/50MHz bus speed (interleaved RAM), 60MHz bus speed (deinterleaved)
3. PowerCenter Pro: up to 60MHz bus speed (no L2 cache dimm installed)
4. PowerTower Pro: 50MHz bus speed (L2 cache dimm had to be removed)
   (some reports indicate there PowerTower Pro 250 systems may have issues. My system is a PTP180 with rev 4 (5000-0121-04) motherboard. Most PTP250s have a rev 5.)

Documentation was complete, sufficient for installation and better than many competitors so I rated it an 8. When I review the printed or final manual version this may be revised. Although the CarrierZIF manual is not available online yet, their previous CPU card PDF manual is online. It's a great way to see in advance how to install a CPU slot card. Since the speed control switch on the CarrierZIF is the same, it will also give you information on speed settings. You can download the std CPU Card slot (MAChSpeed G3) manual here.

I've suggested they put a note on some stock L2 cache dimms being a potential problem in the installation section (it's currently in the troubleshooting section). This may let owners of some Macs with slow L2 cache dimms (8500/120s for instance) know to remove the cache before initial installation. Removing the L2 cache dimm may not be required in all cases but may allow faster Bus speeds. No company could include the procedure required to remove the cache in all Mac models, but it is fairly accessible for most Mac models except the infamous 8500 (see my illustrated guide to 8500 cache removal/replacement).

The next page describes the hardware features and specifications of the card. Or you may use the links below to jump to a specific page.