The Source for Mac Performance News and Reviews

Review: OWC's Mercury ZIFs 350MHz and 400MHz Models Published: 10/17/99

Hardware Features/Specifications/Compatibility

Intro | Benchmarks  | Appl. Tests | Software Controls  | Docs/Installation | Specs/Design | Summary

Hardware Features/Compatibility

Older (pre-Apple G3) Macs that have a CPU card slot can use these ZIF CPU modules if they own an XLR8 CarrierZIF card which has a ZIF socket just like Apple's G3 system motherboards. This which means upgrading to a faster CPU later is a snap. See my Setup Guide to the CarrierZIF for details on the CarrierZIF including installing CPU modules. OWC ZIF CPU/Cache Part Numbers: Here are the part numbers of the Mercury ZIF CPUs and Cache from the two review samples: Mercury 400/200/1MB ZIF CPU: Motorola XPC750 PRX450PE (Sold as 400MHz rated) Cache: SEC KM736V799T-44 Mercury 350/175/1MB ZIF CPU: Motorola XPC750 PRX350PE (350MHz Rated) Cache: SEC KM736V799T-55 Note: Motorola 'X' prefix parts normally mean experimental or not finalized; however I've seen XPC CPUs in B&W G3s and the Grackle PCI/Memory controller in the Beige and B&W G3 is a 'XPC106' part. After determining settings that were reliable with my Macs (I never try to push the razor's edge), these ZIFs were reliable during extensive testing in applications tests and a full Retrospect backup at the speeds listed in this review. Different samples in different Macs could have different maximum bus and CPU speeds. Don't assume you can repeat anyone else's speeds in your Mac. Overclocking is risky and can lead to data loss and/or reliability problems. CPU Temperatures: The following XLR8 Control Panel screens are verification of the speeds and temperatures seen in tests with the Mercury ZIFs: 350MHz ZIF at rated speed (in Genesis): 44C 350MHz ZIF at 400MHz speed (in Genesis): 44C 400MHz ZIF at 433MHz (in Beige G3): 43C Most PowerPC CPUs are rated for 65C maximum operating temperatures, however I do not consider the software utilities reported temperatures as 100% accurate (especially with IBM Copper CPUs which often show temperatures at or below ambient temperature). Consider the temperatures reported as relative, not absolute. If the CPU does overheat, usually you'll know it right away via errors and unstable operation. Compatibility: The Mercury ZIFs when used in a CarrierZIF are compatible with the following Mac models: l [based on the latest XLR8 info]: Apple: 7300, 7500, 7600, 8500, 8600, 9500, 9600 DayStar Genesis MP720 or later, Millennium UMAX S900 & J700. Power Computing PowerWave, PowerTower Pro, PowerCenter, PowerCenter Pro, PowerTower Note: The early CarrierZIF cards were PowerBase compatible (based on a review at MacsOnly and owner reports in my Rate Your G3 Upgrade database) - however the latest CarrierZIF/MAChCarriers are said to NOT be PowerBase compatible. * I recommend PowerTower Pro owners call XLR8 to check compatibility with their logic board. Although XLR8 has revised the CarrierZIF card design and this may be solved now, I still suggest verifying before you buy. I've tested with a PowerCenter Pro (fully tested - but disable 7200 Graphics Accel. extension as noted in the FAQ and PF G3/Powercurve tips pages) and PowerTower Pro 180 (initial boot/checkout tests at 50MHz bus) here successfully, but as noted previously I suggest PowerTower Pro owners contact XLR8 to ensure their motherboard models are compatible. Also check my Rate Your G3 Upgrade database for XLR8 CarrierZIF owner reports (selectable by Mac models) Retrospect Compatibility: I also verified that Retrospect 4.0 backups were error-free. With 'Speculative Processing' disabled a complete backup of a 1.2GB boot volume in the Genesis completed without errors (including verification). The XLR8 control panel default setting for 'Speculative Processing' (often called 'Branch Prediction') is disabled. Dantz (makers of Retrospect) Tech Note 414 reports there is a problem with all pre-Apple G3 systems onboard Ethernet unless you are running the Ethernet extensions from OS 8.6. They also recommend disabling Speculative Processing if you are doing backups or large file copies over a network as a precaution. on the applications performance page you'll see in some cases that setting actually increased performance. Retrospect was the only application I saw that required it, but there could be others that I've not used. I have not tested Adaptec wide SCSI card compatibility but XLR8 has a Tech Note on how to use their software with these cards. The tests in the PowerCenter Pro using the OEM 2930B showed no problems. More information on compatibility issues with other G3 CPU upgrades, see the comments on my CarrierZIF First Look page, the CPU Upgrades area of my FAQ and CPU Reviews page. System Compatibility/Stability Tests: [Beige/B&W G3 owners can skip this section as you don't need a CarrierZIF base card for your systems.] Here is a summary of my tests to date with two models of XLR8 CarrierZIF design cards in four different Mac systems, each chosen for a particular reason: PowerCenter Pro - a good test of maximum bus speed since it was designed for 60MHz 604E bus speeds. The CarrierZIF ran 60MHz bus speeds with no problems in my system. I had previously removed the L2 Cache dimm when running another brand of CPU card. The PowerCenter Pro used the 2MB onboard video (ATI Mach64) and had 80MB of RAM, running OS 8.1. See my previous CarrierZIF review and CarrierZIF reviewfor tests in an PowerCenter Pro. Genesis - This 9500 motherboard (w/512K soldered-in cache) based system has always been picky about cards it likes especially at bus speeds over 45MHz. The CarrierZIF has run 55MHz bus speeds fine in this machine which has 512MB of interleaved RAM. The Genesis system is loaded with dual ATTO SCSI cards (slots 1 and 4), Proformance 3 (slot 6), FUSE capture card (slot 5), boot UW Cheetah disk and 4-drive RAID 0 array. Tests were run using OS 8.1. 9600/350 (aka Kansas/Mach 5 design) - a sore point for many CPU Cards due to CPU voltage differences. The CarrierZIF with XLR8 G3/400ZIF module ran 55MHz bus speeds rock solid with 320MB Interleaved RAM and 60MHz bus speeds with RAM not interleaved. The 9600/350 system has a Radius Thunder3D graphics card, Game Wizard Voodoo2, Jackhammer PCI SCSI card and TurboMax IDE card. Tests were run using OS 8.1. See my previous CarrierZIF review for tests in an 9600/350. PowerTower Pro 180 - My first CarrierZIF review included a test in my PTP 180. With a 50MHz bus speed and interleaved RAM I had to remove the L2 cache dimm but otherwise it ran OK. It would not boot at 55MHz bus (L2 cache removed/RAM still interleaved). XLR8 has revised the card design since my first review to address the PowerTower Pro 250 logic board design but I still suggest you contact them to verify your particular PTP logic board is compatible. I have not yet tested the current revision CarrierZIF cards in my PTP system. For other CarrierZIF/OWC ZIF owner reports, see my Rate Your G3 Upgrade database. As with all CPU upgrades, often times on inquiry I find out there may have been a L2 cache, RAM, speed settings (Bus or CPU speed too high), reversed heatsink clip (see my Setup Guide) or other reason for problems reported, but the database is still a valuable tool. (Note: OWC ZIF owner reports will be found in listings for both CarrierZIF and Other World Computing card brands. Beige/B&W G3 owners should select 'Other World Computing' as the card brand and their Mac model (Beige or B&W G3). Older Mac owners should select 'XLR8 CarrierZIF' as the card brand to find OWC and other ZIF upgrade reports using the CarrierZIF as the base card.) I stress that owners of any card should use it for several weeks at least before posting an entry in my database. Always remember to read the manual completely before installation (and the recommend list of articles noted on the installation page of this review). If there are problems - contact the card vendor immediately, they often can provide a solution or identify the source of the problem.

The next page contains a summary and final comments on these upgrades.

Index of OWC Mercury ZIF Review Pages Intro | Benchmarks  | Appl. Tests | Software Controls  | Docs/Installation | Specs/Design | Summary - or - Back to WWW.XLR8YOURMAC.COM

Copyright © Mike, 1999. All Rights Reserved. All brand or product names mentioned here are properties of their respective companies. Users of the web site must read and are bound by the terms and conditions of use.