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.
AGP 2X? Looks like I might need to pick one up for my old box. I’ve already maxed out RAM and gave it a big fat HD that it’s OK with (unlike most of my P3 PCs, it’s BIOS works happily with any disk drive it seems)
Yeah, AGP 2x… if a card has two notches in the AGP connector like mine in the photo above (perhaps not very well visible), it supports AGP 2x. That is to say, it had better support the AGP 1.0 specification (with AGP 1x/2x speeds) because it can be plugged into an AGP 1.0 slot.
The Radeon 9700 Pro and 9800 Pro were among the few high-end cards which supported AGP 2x/4x/8x; from about 2003 onwards, high-end AGP card almost exclusively only supported AGP 2.0 and 3.0 (AGP 4x/8x) and can’t be used with everyone’s favorite old chipset.
Interestingly, low-end cards like Radeon 9200 series or various GeForce MXs continued to support AGP 2x for much longer.