CrossfireX and SLI from another Point of View!

[expellite]

Hey guys I've got a little problem. I have ASUS P8H77-V LE and it provides CrossfireX in 16x/4x which means the second slot is slower. No this is my question: Can this affect a GPUs performance so much??? I know the difference is obvious when using professional cards but what if I use two standard cards instead of professional ones! the other problem is that the blue slot is PCIe 3.0 and the black one is PCIe 2.0! Now please tell me can I use two Radeon HD 7750 in crossfireX mode or it won't reach its maximum bandwidth! the other thing is that 7750 reference card has a bandwidth of 72GB/s! I hope that could work! Can I utilize two HD 7750s??? By the way I have Core i5 3450 which means PCIe 3.0 is active! I'm currently using a GTX 550 Ti DCU TOP and I'm plannig to buy two 7750s if possible!

 

[4745454b]

You'll be ok. It won't be as fast as 8x/8x, but seeing as the slots will be PCIe 2.0 and not 1.0 it will work. The drop is semi steep, I think you lose around 20%.

 

[expellite]

You'll be ok. It won't be as fast as 8x/8x, but seeing as the slots will be PCIe 2.0 and not 1.0 it will work. The drop is semi steep, I think you lose around 20%.

ok gotcha! What about using a 7770 on X16 and a 7750 on x4??? these cards can work together and no bridge is needed! I hope this could solve two 7750 performance loss! but It has some loss itself!!!!
Hey SLI is not mentioned in ASUS website but Can I use SLI??

 

[ThatsMyNameDude]

Yay!!!! Finally somebody with the same motherboard as me . I run a i7 2600k with a gtx 560 on that mobo. Yes. what you are doing is perfectly fine. tests show that running a 6990 on 8x pcie 2.0 has only around 5fps difference. your single gpu is far much less than a 6970. a 4x pci2 slot will be more than enough for a 7750. Even if there is a problem, it will not be much. remember the test is a 6970 running on a 4x pcie 2.0 slot.

Another thing to note is that the 7750 supports pcie 3.0. that does not mean it saturates a 2.0 slot. it barely touches a 2.0 8x bandwith. The pcie 3 will only come in handy if u overclock that 7750 to the nuts which will barely reach 6970 speeds.

So in conclusion, Yes it is perfectly. FINE. Do not even think about it. If you want some proof then here is some proof of a 6990 running on a 8x lane or a 6970 on a 4x lane. keep in mind that a 6970 is much more powerful that a 7750.

http://www.youtube.com/watch?v=rSfifE2Domo


Wait. update. a 7750 will NOT support crossfire X. sorry to say that. but i have more suggestions. either go with a 6850 crossfire or a 6870 cfx. 6870 is very popular.

Either one will do. As the 6850 slamms even the 7770.

 

[unksol]

7750s CAN be crossfired. In crossfire the cards match the lowest card which means using a 7770 with a 7750 is a waste of money.

You shouldn't crossfire low end cards to start out anyway. You are just asking for driver/game trouble and spending more money when you can get a single better card instead.

Crossfire/SLI should only be used when a single high end card can't drive a high resolution/multi monitor display on it's own, or when you already own one of the cards and need more performance. It's typically a very bad idea to buy 2 bottom end cards to crossfire when a single better card would meet your needs with less complications

 

[expellite]

7750s CAN be crossfired. In crossfire the cards match the lowest card which means using a 7770 with a 7750 is a waste of money.

You shouldn't crossfire low end cards to start out anyway. You are just asking for driver/game trouble and spending more money when you can get a single better card instead.

Crossfire/SLI should only be used when a single high end card can't drive a high resolution/multi monitor display on it's own, or when you already own one of the cards and need more performance. It's typically a very bad idea to buy 2 bottom end cards to crossfire when a single better card would meet your needs with less complications

ok don't worry I'm not going to buy 7750 I just wanted to know about this. you're right I can use HD 7850 instead of two 7750s! this is good! so it's not necessary and I'll buy GTX 650 Ti!

 

[expellite]

Best answer selected by expellite.