is turning off fast write bad?

[thenerd]

i recently turned it off to get some oc'ing stability... 9600xt

 

[Zardoz]

http://www.hardforum.com/showthread.php?t=814800



From Adrian Rojak's site www.rojakpot.com (who by the way is THE authority on bios settings):

This BIOS feature controls the chipset's AGP Fast Write capability. Fast Write is a feature which accelerates memory write transactions from the chipset to the AGP device.

Normally, any data meant for the AGP device must be written to the main memory for the AGP device to read. Fast Write allows the AGP device to bypass the main memory and directly access the data. To do so, the AGP device will act as a PCI device whenever the chipset attempts to write to it. This allows the data to be directly written to the AGP device (like other PCI devices), instead of being written to the main memory first.

As you can see, bypassing the main memory saves time and improves the AGP read performance. However, AGP writes (to the chipset) will not benefit from Fast Writes as it will follow normal AGP protocol and write to main memory.

In addition, while PCI signals are used for Fast Write transactions, the behaviour of those PCI signals has been modified and do not follow PCI specifications. Therefore, this feature may cause problems with some PCI cards.

Therefore, it is recommended that you enable AGP Fast Write for better AGP read performance but disable it if any of your PCI cards start acting funny.

Please note that for AGP Fast Write to work, both motherboard chipset and graphics card must support the Fast Write protocol and the data transfer rate must be at AGP2X or faster.