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Fast Writes

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I'm a little teapot Senior
Dec 17, 2000
Montana, USA
Anybody know how to enable fastwrites with my setup. its on in the bios, but SANDRA says its off. Any ideas.
Sandra might be wrong here. I have it enabled in my bios too and in NvMax and SiSoft Sandra still says its disabled. There are a couple of bugs in Sandra, that might be one of em.
When having FastWrites enabled in the BIOS, or Sidebanding enabled by the Videocard's BIOS...it doesn't necessarily mean that they will be enabled within Windows. The newer Nvidia driver sets disable both SBA and FW even though they're enabled in the BIOS. You can get by the SBA limitation by following the instructions I gave to "DeRose306" here...


To get by the FW limitation...under the same key in the Registry, you can add the following "Binary Value Name"..."EnableAGPFW" (without the quotes). To enable the Binary, the "Value Data" should look like this...

01 00 00 00

...and like this to disable FW:

00 00 00 00
I also question the fastwrites and sideband addressing. Had neither till I edited the vc bios and enabled them. Now sisoft shows them supported and enabled on the card. Did this after reading that many manufacturers where disabling them in order to prevent system conflicts. Ray Adams bios editor works nicely and you can also set the boot up parameters as far as gpu/vmem speeds. Hear tell the new Riva supports Radeon.
i personally havent seen any improvement, but then again i dont play games all that much, niether did i do alot of testing on this subject.
Enabling Fast Writes was originally meant to show an improvement in data transfers that go directly from the CPU to the graphics chip, which doesn't touch such things as "AGP-texturing". 3D-software with very complex 3D-objects requires that the CPU transfers a huge amount of triangle-data to the graphics chip...here is where Fast Writes avoids the stalling detour from the CPU to memory and then from memory to the 3D-chip. The Fast Writes idea is to directly connect CPU and 3D-chip.

The only areas where fast writes seem to benefit an AGPx4 system is on complex geometry scenes with low texture demands, and also helps with increased lighting calculations.

My card and chipset both support Fast Writes (the card also supports SBA), but SBA was disabled in the Leadtek BIOS...to enable it by default (and find out if SBA had any effect on performance), I needed to flash the card with a Nvidia reference BIOS. Running 3DMark, my scores are just slightly lower with both enabled...but in games like UT and CS I gain about 3-5 FPS (not much of an improvement as far as FPS), but in actual game play...I can tell a noticeable difference.;)