Having recently read the preview of the 9600GT at Anandtech, one of the things that stood out from that article was how SLI seemed to do better than Crossfire on the games that were tested. Crysis was the only game that was used in both this article and that one, and 3850's were run in Crossfire for the earlier article, not 3870's. Nevertheless, it looks like Crossfire performance gains going from 1 to 2 ATI cards is now on a par (with the new AMD/ATI drivers) with going from 1 to 2 Nvidia cards.
Perhaps this will prove to be the reason for AMD/ATI selecting the tests they did in this preview. CrossfireX does about as well SLI on these particular games?
(Though we'll not see the results, we know that Derek is trying these new ATI drivers out on his Skulltrail system, if it's possible. ;-) )
You've listed the 4-way CF over 1 card gain as 268%.
It should be 368%. (95.2/25.3 = 3.68)
The numbers are confusing, comparing 3-way to 2-way etc. Why do that, makes more sense to compare 3-way to 1-way. Then it's easy to compare to the perfect scaling of 200, 300, 400%.
I got confused by it to but the Test Bench isn't what they listed on the page. Either that's a Typo or that's just supposed to refer to the Nvidia Benchmark that they did with the Tri-SLI
Yeah, it looks like they entered the test setup from the Nvidia article rather than the one used in this article. It would make sense if they entered both test setups but not to completely exclude the AMD setup used for most of the tests.
Good catch for Anandtech! AMD told you it was a Phenom board but you saw it was really a QX9650. The company must be in dire straits to try a trick like that. Sad.
Hi, alot of people are still playing WoW, me included. I just bought the Samsung 245B, a wide 24" screen. I'd love to see a cpu+gpu update for the wow guide. If i should invest in an extra 8800GTS or a new Core2 or AMD Phenom cpu.
Previous 3870 CrossFire vs. 3870X2 reviews have shown that the X2 performs better than two standalone 3870s in CrossFire. So using "2 GPUs" as the X2 only might be deceptive. I want to see:
One 3870
Two 3870s
Three 3870s
One 3870X2
One 3870X2 + one 3870
Two 3870X2s
(I don't think there is any board that could take four plain 3870s.)
Simply because from previous reviews, the "one to two" delta is much higher for X2 than for two plain 3870s. Another question is if the delta from one to two 3870s is the same as one to two 3870X2s. Based on previous X2 reviews, it looks like by all rights, the system really sees the X2 as a single double-fast GPU.
Except when you use all four slots, they all drop to x8. And, yes, you would need a case with 8 back-panel slots, including one beyond the 'bottom' of the card. (Or you'd need to hack your cards to be single-slot.)
"From AMD's explanation it sounds like there's still a lot of work to be done on the CrossFireX driver. While we can expect to see its public debut in March, it seems like it'll be a while before we're anywhere close to ideal scaling. We've found ourselves in this position with many-GPU designs in the past, at least the players are taking things a bit more seriously this time around."
You guys, and many others have been talking about how well quad core CPUs scale(or dont) in a none server, are you really all that surprised to find that quad GPUs would be similar ?
I have been long suspecting that while the PCIe specification is absolute in how much bandwidth a number of PCIe lanes are supposed to have total, that motherboard manufacturers have been skimping as to how much they are allowing those lanes use. Maybe this is just now biting them in the behind ? Or maybe I am just being silly . . . ; ) Either way, system details are not exactly forthcoming here.
"What were 70 - 100% gains from 1-to-2 GPUs are more than cut in half, becoming 30 - 45% gains when you add a third GPU"
this should be expected...
If each card provides 50fps in an ideal case...
1card at 50 fps
2card at 100fps = 100% improvement over 1 card
3card at 150fps = 50% improvement over 2 cards
4card at 200fps = 33% improvement over 3 cards
The most it can possibly provide is 100%, 50%, 33% improvements at 2,3,4 cards.
exactly what i was thinking ... cod almost scales ideally right up to 4 gpu's ... that 'somewhat reasonable gains' statement would fit HL2, which is scaling with every gpu added but the benefit diminishes. cod is scaling almost optimal:
i'd like to see how it handles mismatched cards in 3/4 way configs. another site did a crossfire review with a hd 3870 paired with a hd 3850 and their combined performance approached a hd 3870x2.
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28 Comments
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Spacecomber - Friday, February 22, 2008 - link
Having recently read the preview of the 9600GT at Anandtech, one of the things that stood out from that article was how SLI seemed to do better than Crossfire on the games that were tested. Crysis was the only game that was used in both this article and that one, and 3850's were run in Crossfire for the earlier article, not 3870's. Nevertheless, it looks like Crossfire performance gains going from 1 to 2 ATI cards is now on a par (with the new AMD/ATI drivers) with going from 1 to 2 Nvidia cards.Perhaps this will prove to be the reason for AMD/ATI selecting the tests they did in this preview. CrossfireX does about as well SLI on these particular games?
(Though we'll not see the results, we know that Derek is trying these new ATI drivers out on his Skulltrail system, if it's possible. ;-) )
Zoomer - Thursday, February 21, 2008 - link
Are you allowed to only test these games, or allowed to publish and talk about these games only?I don't see how ATi can enforce such a requirement. *cough* ghost *cough*
Wirmish - Thursday, February 21, 2008 - link
PC Perspective also test the beta-CrossFire-X.Their system is identical, except for the hard disk.
http://www.pcper.com/article.php?aid=523&type=...">http://www.pcper.com/article.php?aid=523&type=...
RÉSULTS:
Bioshock
Anand (0xAA/0xAF) -> 2=63, 3=87, 4=93
PCPer (0xAA/8xAF) -> 2=65, 3=84, 4=92
Call of Duty 4
Anand (4xAA/16xAF) -> 2=50, 3=72, 4=93
PCPer (4xAA/ 8xAF) -> 2=43, 3=56, 4=64
Unreal Tournament 3
Anand (0xAA/16xAF) -> 2=84, 3=113, 4=115
PCPer (0xAA/ 8xAF) -> 2=58, 3=54, 4=58
How do you explain these results ?
POWER CONSUMPTION - ENTIRE SYSTEM
Anand (Bioshock) -> 2=361W, 3=406W, 4=538W
PCPer (CoD 4) ----> 2=407W, 3=527W, 4=663W
Why didn't you choose the hungriest game to calculate the consumption of the system ?
Paracelsus - Thursday, February 21, 2008 - link
You've listed the 4-way CF over 1 card gain as 268%.It should be 368%. (95.2/25.3 = 3.68)
The numbers are confusing, comparing 3-way to 2-way etc. Why do that, makes more sense to compare 3-way to 1-way. Then it's easy to compare to the perfect scaling of 200, 300, 400%.
mechwarrior1989 - Thursday, February 21, 2008 - link
I got confused by it to but the Test Bench isn't what they listed on the page. Either that's a Typo or that's just supposed to refer to the Nvidia Benchmark that they did with the Tri-SLIkalrith - Thursday, February 21, 2008 - link
Yeah, it looks like they entered the test setup from the Nvidia article rather than the one used in this article. It would make sense if they entered both test setups but not to completely exclude the AMD setup used for most of the tests.Anand Lal Shimpi - Thursday, February 21, 2008 - link
Woops :) Fixed :)Take care,
Anand
Arbie - Thursday, February 21, 2008 - link
Good catch for Anandtech! AMD told you it was a Phenom board but you saw it was really a QX9650. The company must be in dire straits to try a trick like that. Sad.donkeycrock - Thursday, February 21, 2008 - link
The graph is the best and most effective one i've seen in anybody's review in a long time. cheers and well donebrunis - Thursday, February 21, 2008 - link
Hi, alot of people are still playing WoW, me included. I just bought the Samsung 245B, a wide 24" screen. I'd love to see a cpu+gpu update for the wow guide. If i should invest in an extra 8800GTS or a new Core2 or AMD Phenom cpu.
regards,
Brunis
PhantomKnight - Thursday, February 21, 2008 - link
Sorry getting used to the comment posting.This would have helped.
3 x Radeon HD 3870 (2 X2 + 1)
NicePants42 - Thursday, February 21, 2008 - link
I was also wondering what that meant. Looks like two 3870x2s plus one 3870.I was also a little confused about the system setup - looks like they were using nVidia hardware and drivers...
tynopik - Thursday, February 21, 2008 - link
obviously it's a typo and they meant 1 X2 + 1PhantomKnight - Thursday, February 21, 2008 - link
Am I alone in being confused, i thought that 2 times 2 plus 1 is equal to 5.Anonymous Freak - Thursday, February 21, 2008 - link
Previous 3870 CrossFire vs. 3870X2 reviews have shown that the X2 performs better than two standalone 3870s in CrossFire. So using "2 GPUs" as the X2 only might be deceptive. I want to see:One 3870
Two 3870s
Three 3870s
One 3870X2
One 3870X2 + one 3870
Two 3870X2s
(I don't think there is any board that could take four plain 3870s.)
Simply because from previous reviews, the "one to two" delta is much higher for X2 than for two plain 3870s. Another question is if the delta from one to two 3870s is the same as one to two 3870X2s. Based on previous X2 reviews, it looks like by all rights, the system really sees the X2 as a single double-fast GPU.
Goty - Thursday, February 21, 2008 - link
The MSI K9A2 Platinum can. =)Actually, I think that's the same motherboard used in this review.
Anonymous Freak - Tuesday, February 26, 2008 - link
Except when you use all four slots, they all drop to x8. And, yes, you would need a case with 8 back-panel slots, including one beyond the 'bottom' of the card. (Or you'd need to hack your cards to be single-slot.)strikeback03 - Friday, February 22, 2008 - link
How many cases have the openings on the back for 4 dual-slot cards?yyrkoon - Thursday, February 21, 2008 - link
"From AMD's explanation it sounds like there's still a lot of work to be done on the CrossFireX driver. While we can expect to see its public debut in March, it seems like it'll be a while before we're anywhere close to ideal scaling. We've found ourselves in this position with many-GPU designs in the past, at least the players are taking things a bit more seriously this time around."You guys, and many others have been talking about how well quad core CPUs scale(or dont) in a none server, are you really all that surprised to find that quad GPUs would be similar ?
I have been long suspecting that while the PCIe specification is absolute in how much bandwidth a number of PCIe lanes are supposed to have total, that motherboard manufacturers have been skimping as to how much they are allowing those lanes use. Maybe this is just now biting them in the behind ? Or maybe I am just being silly . . . ; ) Either way, system details are not exactly forthcoming here.
skiboysteve - Thursday, February 21, 2008 - link
... What?Pirks - Thursday, February 21, 2008 - link
Do they speak English in "what"? (C) Pulp FictionNever mind, just kidding :)
Griswold - Thursday, February 21, 2008 - link
What!?skiboysteve - Thursday, February 21, 2008 - link
"What were 70 - 100% gains from 1-to-2 GPUs are more than cut in half, becoming 30 - 45% gains when you add a third GPU"this should be expected...
If each card provides 50fps in an ideal case...
1card at 50 fps
2card at 100fps = 100% improvement over 1 card
3card at 150fps = 50% improvement over 2 cards
4card at 200fps = 33% improvement over 3 cards
The most it can possibly provide is 100%, 50%, 33% improvements at 2,3,4 cards.
Noting that, COD4 scales incredibly well.
dustwalker13 - Thursday, February 21, 2008 - link
exactly what i was thinking ... cod almost scales ideally right up to 4 gpu's ... that 'somewhat reasonable gains' statement would fit HL2, which is scaling with every gpu added but the benefit diminishes. cod is scaling almost optimal:gpus - max scaling - actual scaling
2gpu - 100% - 98%
3gpu - 50% - 44%
4gpu - 33% - 29%
RamarC - Thursday, February 21, 2008 - link
i'd like to see how it handles mismatched cards in 3/4 way configs. another site did a crossfire review with a hd 3870 paired with a hd 3850 and their combined performance approached a hd 3870x2.Bladen - Thursday, February 21, 2008 - link
I'll say.I am very surprised to see "unfinished" drivers and tech preforming almost optimally, albeit in only 1 test case.
I think AMD should heavily encourage Infinity Ward to licence out COD4's engine.
Griswold - Thursday, February 21, 2008 - link
"I think AMD should heavily encourage Infinity Ward to licence out COD4's engine."Oh please, no!
Samus - Thursday, February 21, 2008 - link
Yea, frak that. COD4's engine doesn't have the feeling or capability of the source engine, which scales great (except for the 4th GPU I suppose.)With more tweaking, the Source engine is most ideal. Obviously they shouldn't target Crytek's engine, though.