Tweak Guide problem with ATI video cards

Wednesday May 14, 2003

I would like to personally thank Terry Makedon & Raymond Skarratt at ATI for their help in this.

The original problem is listed below. Here is the fix. After applying the regedit file and BEFORE rebooting. Navigate to the following:

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management

Change the SystemPages value (hex) to 0xffffffff (you just have to type 8, f 's)

Here is the regedit file: atifixtweak.reg

Now, here is where I'd like to request your input. You may notice a slight performance hit. What we need to try and do is get the numbers in the tweak as low as possible for max performance. The number as it stands is 4294967295 (hex = ffffffff). My original number (and where I had the problem) was 1585152 (hex = 183000). Hopefully, with your help, we can find a lower number that will work.

contact me

***update May 17, 2003

At least a dozen people wrote in to say that ATI or someone else told them to change the following:

Start > Settings > Control Panel > System > Advanced > Performance Settings > Advanced > change Memory usage to Programs.

That IS the LargeSystemCache setting. Checking the "Programs" button disables the LargeSystemCache registry key, setting it to System Cache enables it.

Some of the folks from Rage3d asked for benchmarks so here they are!

System Specs

ProcessorP4 2.26GHz
MotherboardAsus P4PE
Memory512mb Corsair DDR333
Video CardATI 9500 Pro
Hard DriveWD 80gb SE

Test was run using 3dMark03 since the folks involved with this issue seem to consider that their benchmark of choice. Nothing was overclocked. 3dMark03 was run at 1024x768 at default settings except test were run 3 times.

 Test #1 Test #2Test #3
LargeSystemCache offoff on
System Pages 0xffffffff183000 0xffffffff
Score 3675 3674 3677

I consider the difference in scores to be statistically insignificant in light of the fact that the test has only been run on one machine.

-----------------------------------Original Problem-----------------------------------

I recently purchased a ATI 9500 Pro video card. Upon installation of the card I immediately began getting Delayed Write Errors. I have narrowed down the problem to this section of tweaks. I believe the problem lies with the entry highlighted in red. You should delete all these lines from the downloadable .reg file until I have had a better chance to research it.

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Session Manager\Memory Management]

Here are the specs of the system:

Motherboard Asus P4Pe
CPUP4, 2.26
Memory512Mb, Corsair DDR333
Video CardATI 9500 Pro
DriversCat 3.2

 The odd thing is this. The card it replaced was a ATI 8500DV. I had used both the Cat 3.1's and the Cat 3.2's and did not have this problem. I also did a clean install, backed up with Ghost, and then applied this tweak with the same result. I had heard that some had problems with the LargeSystemCache tweak but could not confirm it. As I stated, I have only narrowed it down to the above 3 entries at this time. If you have any info on this please email me!