Crossfire 5770 or single 5870

Zombie01

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Hey guys,

First post but have been reading the forums for a little while.

I recently rebuilt my rig and replaced my old 8800 gt sli with crossfire 5770 only to find out that my motherboard supports one x16 and the second card is x4 :(

Would it be better to get a single 5870 or possibly a new motherboard that supports 2 x16 cards?

Thanks!
 

Dougx1317

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You shouldn't have a problem running the 5770's at 16x/4x. Here are two reviews showing how the 5870 and GTX480 are barely affected. The version of PCI-e does make a difference. What version of PCI-e is your motherboard?

http://www.techpowerup.com/reviews/AMD/HD_5870_PCI-Express_Scaling/1.html
"...we will green-signal installing a third accelerator for some 3-way ATI CrossfireX action, or 2-way CrossfireX on entry-level Intel P55 motherboards with the second x16 slot electrically x4 (running in 1.0 mode)"

http://hardocp.com/article/2010/08/25/gtx_480_sli_pcie_bandwidth_perf_x16x16_vs_x4x4/
"Even with all the data that GTX 480 SLI is pushing across the PCIe bus, x4/x4 is NOT a bottleneck in a single display setup at 2560x1600 with AA enabled."
 

Zombie01

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Thanks guys. I would be returning these cards so I would have about $300 to spend on a new single card. I'm not very familiar with the 560 ti. What do you guys think is the best bang for your buck at that price range?
 

Dougx1317

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That motherboard has PCI-e 2.0 slots. You should have no problem running them at 16x/4x. If you'd rather get a single card, that's up to you. The GTX560 Ti is a great card for the money. Either the GTX560 Ti or the 5870 will cost you more than the 5770's though.
 

Zombie01

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I actually had the 5770s running crossfire but the performance wasn't what I expected from those 2 cards. The rift beta played at roughly 30fps, which seemed kind of low to me.

to my understanding it is because the 2nd slot runs at 4x.

They are great cards but I have been reading other posts and it looks like my money would best be spent buying a single card that's better or comparible to running both 5770s, which I'm guessing would be the hd6950 or 560ti?

I apologize for the newbness of the questions. Its been a while since I've bought parts and just want to make sure I'm getting the best performance
 

Zombie01

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I guess what I'm wondering is with either card will I see performance increases from the previous crossfire setup I had? If I really won't see a difference then I may as well keep the cards. Thanks a lot guys