Difference in Crossfire 16/16 & 8 / 8

[Viensterrr]

Hello everyone,
it would be to see if there is a big difference in a Crossfire (SLI for green) connected to a X38 (16x/16x) and P45 (8x/8x)? What are the loss of performance? Is it worth it to Crossfire on a P45?

Thank you!

[kiLLer]

I think there is a difference of a few% (5-10% maybe? Not more than 15% I think) You can also sell your HD4870 and take a HD4870X2 or GTX295. (must do the calculation to see if it is interesting)

[Marthaz]

P45 vs X38: Quid Crossfire performance in practice?

With the advent of the HD4800 very moderate prices, the temptation to succumb to the joys of the Multi-GPU is great. But then, who said said CrossFire motherboard compatible, then how can you find among the jungle of chipsets? Since 2 years now, Intel offers processors the most interesting for the players, so we decided to study the behavior of two CrossFire chipsets recent, most popular of the founder of Santa Clara. On the one hand the young P45 Express and the other X38 Express a little older and expensive. Both have of course a native of PCIE 2.0, only where the first supports only 8 times 2 lines Multi-GPU, the second brings in twice with 2 times 16.

[David23]

Especially must be careful, your power supply may be a slight auntie for a duo in 4870 and a Quad overclock. it is not bad but it pump the animals there. the problem with the 5xx is that Watts is at the limit where you can try but it might be just to see.

[ApPy10]

In fact, the effectiveness of 8X/8X depends mainly on the bandwidth. If you play at 1024 * 768 at an old game that requires little power, the gain will be negligible 16X/16X now if you play in 1920 * 1200 AA4X AF16X or 2560 * 1600 AA4X AF16X to games like Crysis and bouffeur other power chart (3DMark Vantage mode thoroughly also, for example), the performance will collapse, and it can greatly exceed the 15% mostly on mini FPS or final, your crossfire is less efficient than a single 16X graphics card in terms of fluidity.

Yet the purpose of a crossfire is just to play games unplayable with a single card and can save the graphics options to bottom right resolution (1680 * 1050 great mini in general) or simply to play Thursday in the future (so that demand in general more power).

So for me the crossfire 8X/8X v2.0 no sense

Power PC that damage is not taken into account FPS mini, because it is often that brings down the average, you can very well have scenes that 16X/16X fluid, and then have scenes cut (unlike 16X/16X), so that a difference of 20% between the 2 may very well result in something like:

• 16X/16X => 60 fps
• 8X8X => 58 FPS 8X8X => 58 fps

• 16X/16X => 45 FPS
• 8X8X => 25 FPS 8X8X => 25 fps

• 16X/16X => 50 fps
• 8X8X => 45 FPS 8X8X => 45 fps

[Viensterrr]

Thank you all, that is a X38 better than a P45 but I think it is not really the time to change the mobo.

PS it was a question that turned my head and I have a clear vision. I had no intention, at least now make a crossfire


I thank you all.