x800xl memory speed...confused

[Actuary]

Hey all, I think I know the answer to this, but I'll ask anyway. All the x800xl cards on newegg are listed at specs something like 400 core/980 memory. Mine, according to ATITool, is 400/490 stock. I'm guessing to figure out the memory speed it's 2x the speed listed by ATITool...can someone explain why? Hah, how embarrassing that I don't know

 

[Willseyvilleny]

its ddr memory. Your memory is going to be an effective speed of 980 mhz when you take into account that it will drop twice per clock cycle, atitool talks in raw terms of mhz. your not being ripped off or anything of the sort, now see how far you can push it, im at 540/560 with my x800xt aiw

 

[Actuary]

I had a feeling it had something to do with the DDR memory. Unfortunately, I probably won't be able to push it any further unless I get an ATI Silencer, I'm up to 410/520 up to 75C. Anymore and ATITool detects occasional artifacts.