crossfire question: asus 4850 with an asus 4850x2

yes

@rangers,

For crossfir purposes does the X2 count as one card or two under XP as i thought XP has a two card limit or have i been told wrong ?

Mactronix

AFAIK yes XP has a 2-GPU limit, so a 4850X2 is all you get because it counts as 2 GPUs. On Vista, it should work, and they don't even have to be from the same manufacturer, I think.

I think I'd prefer a single HD 4870X2 to a setup with HD 4850X2 + HD 4850. I suspect it will cost about the same, two GPUs are better supported than 3, and the drivers for a single HD 4870X2 have already been tested by plenty of people. Wait for benchmarks if you can...

BTW, if you're planning to buy a HD 4850 now, you may want to know that you can also combine it with a HD 4870. The result is better than HD 4850 Crossfire, there's no dumbing down.

Yes. You can also crossfire that 4850X2 with a 4870. There doesn't seem to be as much optimization for 3 way crossfire as there is for 2 way crossfire since it was introduced with the 3800 series

mactronix said:

@rangers,

For crossfir purposes does the X2 count as one card or two under XP as i thought XP has a two card limit or have i been told wrong ?

Mactronix

i dont know, never been flush enough to have crossfire

Thanks for that aevm, i dont know what OS cwconrad78 is using but i thought it worth mentioning.
You say that the 4850 +4870 combo is better than a 4850 + 4850 set up, yet i have seen benchmarks that show there isnt that much in it, can you think of a reason for this ? There hasnt been a driver issued since the reviews and i guess its possable the prices have leveled up a bit to make it worth while, however when i saw these results (A week or two ago) the extra cost wasnt justified by the performance.

Mactronix

The reason there isn't much difference is because CF always goes by the lowest freq card and then drags the second card down to it's frequencies, so basically you'll be running a 4870 at 4850 speeds.

I noticed this when i first overclocked my CF setup, so i'm guessing it's the same for everyone.

Yeah, you guys are right. My bad, I should have looked at more benchmarks. This review shows that HD 4870+HD 4850 is a silly combination.
http://www.hardwarecanucks.com/forum/hardware-canucks-reviews/9159-ati-hd4870-hd4850-crossfire-performance-review.html

mactronix said:

Thanks for that aevm, i dont know what OS cwconrad78 is using but i thought it worth mentioning.
You say that the 4850 +4870 combo is better than a 4850 + 4850 set up, yet i have seen benchmarks that show there isnt that much in it, can you think of a reason for this ? There hasnt been a driver issued since the reviews and i guess its possable the prices have leveled up a bit to make it worth while, however when i saw these results (A week or two ago) the extra cost wasnt justified by the performance.

Mactronix

there will be a new driver in the next couple of day's i think