In a previous post, I wrote that a Radeon 9800 XT can’t be used with a 440BX chipset because it’s based on a R360 chip, newer than the R350 used in Radeon 9800 Pros. The reality turns out to be a little more complicated.
For reasons that I won’t go into now, I had to remove the heatsink/fan assembly from a normal-looking Radeon 9800 Pro, a card manufactured by Sapphire sometime at the very end of 2004 or the very beginning of 2005 (given that the PCB indicated week 52 of 2004):
Once I removed the heatsink (and cleaned off a thin residue of thermal paste), I found this:
A R360 GPU… Apparently once the Radeon 9800 XT was released, ATI stopped manufacturing the R350 chip and used the R360 in both the 9800 XTs as well as the 9800 Pros. Therefore the 9800 Pro boards manufactured in 2004 typically used a R360 chip, even though the model designation did not change.
The 9800 Pro boards used slower memory and therefore couldn’t reach the 9800 XT performance levels, even though the BIOS could be flashed and made to look like a 9800 XT. Still, the performance could be increased somewhat.
At any rate, it’s obvious that the R360 GPU does work in AGP 2x systems, even though no Radeon 9800 XTs with AGP 2x support do appear to have been made.