Interex MACh Speed G3 Computer Hardware User Manual


 
Miscellaneous Performance Notes
Many factors effect the performance of the CPU card.
using high quality expansion products, cables and RAM
will ensure that you have a system that can perform much
faster with a “tuned” MACh Speed upgrade.
Any speed can be set for any CPU, but a CPU will gener-
ally only operate at 20% more than its manufacturer rated
speed.
Most of the logic boards supported by the MACh Speed
have a maximum Bus Speed of around 50 MHz.
The CPU operating speed and the cache operating speed
are linked by the BUS speed on the card. The final oper-
ating speed of each is determined by the its Ratio to the
card’s BUS speed.
CPU operating clock speed is determined by:
BUS Ratio X BUS Speed = CPU speed in MHz.
• Once the MACh Speed G3 Upgrade Card is installed, the
Motherboard Level 2 cache becomes a Level 3 cache.
Since the Motherboard cache is smaller than the Level 2
cache, it will not add to the system performance. If possi-
ble (as in the 8500/7500), you should remove the mother-
board cache.
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2. Uncheck automatic startup of the cache.
To avoid having problems with boot-up if you select “too
fast” of a setting, deselect the “Enable backside cache at
startup box”. You can enable automatic start-up later
once you have found the optimum setting.
3. Select “Advanced Options:
Set the Cache control to the next highest Ratio. some set-
tings are not available for some card as the setting would
result in speeds much too high for the cache.
Select “OK”
Setting the Cache Ratio for Maximum speed
4. Restart the backside cache
In the main window, select “Enable Now”
If you freeze at this point, then you have selected too fast
of a setting for your backside cache. It is possible to adjust
the CPU settings on the card to a slower setting, then
using a higher ratio on the backside cache.
Your system should be able to run memory tests such as
TechTool Pro or DayStar’s PowerControl Testing software
overnight consistently to operate at the higher speeds.
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