Increase cache speed for certain G4 upgrade cards
Nov 20, '02 09:44:11AM
Contributed by: jbouklas
New PowerLogix and Sonnet upgrades are available for G4 systems. These upgrades have 1 to 2 MB of L3 cache on them. PowerLogix chips require a special piece of software for the L3 cache to be recognized in OS X (called Cache Control X). Here is a way to overclock your cache using the Terminal:
- Install the software provided by PowerLogix
- Type in sudo plxcache -off in the Terminal
- Type in sudo plxcache -r 3.5 where 3.5 is the ratio controlling the cache speed in regard to the bus speed (3.5 gives you 229 MHz cache in a 100 MHz system bus, etc)
- Experiment until you can achieve the highest speed with stability
Check the GUI software that they give you to determine the speed. If you set the speed too high, you will have to restart your machine. There is no damage done at all and it can run very safely at a higher speed. If you want to set the speed to change when your computer boots, make an AppleScript as follows: do shell script "plxcache -off" password ¬
"ADMIN PASSWORD" with administrator privileges
do shell script "plxcache -r 3.5" password ¬
"ADMIN PASSWORD" with administrator privileges
Save it as run-only and put it into your login items. This works for Sonnet and PowerLogix chips alike.
[Editor's note: I don't have a G4 upgrade card to test this with ... insert standard "backup before experimenting" advice here!]
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