Accelerate Your Mac! - Review of Other World Computing's Mercury 350/400 ZIFs

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

Software Cache Control Features

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

Cache Control Software

The OWC Mercury ZIF CPU upgrades are OEM models as previously mentioned and come with no software controls for cache enabling, since when installed in Apple Beige or B&W G3s, the Apple ROM enables the backside cache without any need for 3rd party software. To use these ZIF CPU models in CPU Card slot (pre-G3) Macs; you need to have an XLR8 CarrierZIF card which comes with XLR8's Cache Control panel. This page has information on the XLR8 software provided with the CarrierZIF card.
Note: From what I have seen in real world applications tests, backside cache speed is not a primary factor in performance so don't push the bleeding edge on cache speed as it can affect reliability.

Installing the Software (CarrierZIF users only):

The XLR8 software installer automatically places the cache control and extension in the system folder. After a reboot, it tests the backside cache automatically and reports what it suggests is the maximum reliable cache speed (but offering you the option to manually set the speed to another setting). Often this speed may not be reliable in my experience, so I suggest keeping the cache at 1/2 the CPU speed or near the cache rating. Running the cache too fast is a sure way to crash your Mac, possibly causing disk corruption. Cache speed is not a major factor in real world performance - so keep the cache speed at 1/2 the CPU speed for best reliability.

Mercury 350MHz ZIF (in Genesis)

Mercury 400MHz ZIF (in Genesis)
400MHz
(Note: the 350 running at 400MHz reported the same temps as the 400Mhz)

XLR8 CarrierZIF Control Advanced Settings:

Clicking on the 'Advanced' tab will allow you to set the backside cache speed to manual (you select a speed) or automatic. There is also an option to enable or disable (default) Speculative Processing of the G3 CPU and to disable (default) any motherboard cache (a nice feature for owners of solder-in cache like the 9500, some 9600s and Umax machines). For Macs with L2 Cache dimms, I highly recommend removing them before installing a G3 upgrade.

As noted previously, it is recommended that you disable Speculative Processing in older Macs to reliably run software like Retrospect (which backed my Genesis drive flawlessly). I saw no other need to disable it otherwise, but in previous tests I've done, it actually improved performance a bit in Photoshop, but applications like Infini-D showed a 4% or so increase in rendering times with Spec. Proc. disabled.

The 'Performance Tips' tab contains notes on faster cache speed settings. The 'Support' tab lists XLR8's contact information including toll-free tech support line and web site address (a nice feature).

Beige G3 Speedmeter Results: Since no cache control software is needed for Apple G3 systems using these ZIFs, I used Powerlogix's free Speedmeter utility to verify the speed settings and temperature.

Note: As I've mentioned many times in the past in the front page news, I don't believe the CPU junction temperatures are accurate (literally), especially with the new Copper CPUs (IBM 300Mhz and higher are all copper based now - get our exclusive PPC Checker to test yours).. For instance, a (laughable) 8 degrees C was reported from a 400MHz copper G3 in a previous CarrierZIF review. Of course there is no way a 400MHz CPU can be running below ambient room temperature without active cooling.

Since the temperature reporting software just reads a register on the CPU unless a company performs extensive tests and applies a 'calibration factor' to the reading the temperatures are of little use in my opinion. BTW - most G3 desktop CPUs are rated for 65C junction temperatures (PB G3 models use an 85C version I hear).

The next page describes the documentation and installation instructions supplied with the card. Or you may use the links below to jump to a specific page.

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.

The Source for Mac Performance News and Reviews
Review: OWC's Mercury ZIFs 350MHz and 400MHz Models Published: 10/17/99
Software Cache Control Features
Intro \| Benchmarks \| Appl. Tests \| Software Controls \| Docs/Installation \| Specs/Design \| Summary
Cache Control Software
The OWC Mercury ZIF CPU upgrades are OEM models as previously mentioned and come with no software controls for cache enabling, since when installed in Apple Beige or B&W G3s, the Apple ROM enables the backside cache without any need for 3rd party software. To use these ZIF CPU models in CPU Card slot (pre-G3) Macs; you need to have an XLR8 CarrierZIF card which comes with XLR8's Cache Control panel. This page has information on the XLR8 software provided with the CarrierZIF card. Note: From what I have seen in real world applications tests, backside cache speed is not a primary factor in performance so don't push the bleeding edge on cache speed as it can affect reliability. Installing the Software (CarrierZIF users only): The XLR8 software installer automatically places the cache control and extension in the system folder. After a reboot, it tests the backside cache automatically and reports what it suggests is the maximum reliable cache speed (but offering you the option to manually set the speed to another setting). Often this speed may not be reliable in my experience, so I suggest keeping the cache at 1/2 the CPU speed or near the cache rating. Running the cache too fast is a sure way to crash your Mac, possibly causing disk corruption. Cache speed is not a major factor in real world performance - so keep the cache speed at 1/2 the CPU speed for best reliability. Mercury 350MHz ZIF (in Genesis) Mercury 400MHz ZIF (in Genesis) (Note: the 350 running at 400MHz reported the same temps as the 400Mhz) XLR8 CarrierZIF Control Advanced Settings: Clicking on the 'Advanced' tab will allow you to set the backside cache speed to manual (you select a speed) or automatic. There is also an option to enable or disable (default) Speculative Processing of the G3 CPU and to disable (default) any motherboard cache (a nice feature for owners of solder-in cache like the 9500, some 9600s and Umax machines). For Macs with L2 Cache dimms, I highly recommend removing them before installing a G3 upgrade. As noted previously, it is recommended that you disable Speculative Processing in older Macs to reliably run software like Retrospect (which backed my Genesis drive flawlessly). I saw no other need to disable it otherwise, but in previous tests I've done, it actually improved performance a bit in Photoshop, but applications like Infini-D showed a 4% or so increase in rendering times with Spec. Proc. disabled. The 'Performance Tips' tab contains notes on faster cache speed settings. The 'Support' tab lists XLR8's contact information including toll-free tech support line and web site address (a nice feature). Beige G3 Speedmeter Results: Since no cache control software is needed for Apple G3 systems using these ZIFs, I used Powerlogix's free Speedmeter utility to verify the speed settings and temperature. Note: As I've mentioned many times in the past in the front page news, I don't believe the CPU junction temperatures are accurate (literally), especially with the new Copper CPUs (IBM 300Mhz and higher are all copper based now - get our exclusive PPC Checker to test yours).. For instance, a (laughable) 8 degrees C was reported from a 400MHz copper G3 in a previous CarrierZIF review. Of course there is no way a 400MHz CPU can be running below ambient room temperature without active cooling. Since the temperature reporting software just reads a register on the CPU unless a company performs extensive tests and applies a 'calibration factor' to the reading the temperatures are of little use in my opinion. BTW - most G3 desktop CPUs are rated for 65C junction temperatures (PB G3 models use an 85C version I hear).

The next page describes the documentation and installation instructions supplied with the card. Or you may use the links below to jump to a specific page.

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.