Crossfire support is x16 and x4

[GoldenI]

Hey all,

With Battlefield 3 coming up, I want to upgrade my system a little bit (I plan on buying 8 GB of RAM and maybe a new processor, too) so I have been thinking about getting another graphics card.

Right now I have an AMD Radeon 6850 but want another one, however, my motherboard only supports crossfire in x16, x4, and x1. I am just curious if I would notice an increase a decent increase in performance if I went out and bought another 6850. I am assuming the increase would be marginal, if any.

 

[Mvx15n]

I did 16x4x i5-760with two 6950 and the performance in bfbc2 and 3dmark went up around 1,5x over a single but when changed the cpu i7-2600k and switched to 8x8x it went over 2x performance... While crossfire is not running 100% smooth in bfbc2 in bf3 runs perfectly.

Take into account that bf are cpu intensive games and you might be cpu limited too

 

[purple stain]

Running a card in a x4 slot doesn't have a huge impact on performance as you would think.Although it really depends on the card but for the 6850's sake you would only loose about 5-10fps compared to a x16 slot.Not that big of a difference so I wouldn't worry about it.

I would suggest saving instead of buying the extra 4GB of RAM for a new CPU or O.C.ing higher if you can.BF3 is very CPU demanding and it requires a very fast quad core CPU.I upgraded from 4GB to 8GB of RAM and I don't notice any difference.I've never seen the RAM usage go above 3GB so I think you will be fine at 4GB for now.

What is the make/model of your PSU?

 

[jyjjy]

Yeah, it should be fine for a card like the HD6850 on a board with PCI-E 2.0 slots.

 

[GoldenI]

Running a card in a x4 slot doesn't have a huge impact on performance as you would think.Although it really depends on the card but for the 6850's sake you would only loose about 5-10fps compared to a x16 slot.Not that big of a difference so I wouldn't worry about it.

I would suggest saving instead of buying the extra 4GB of RAM for a new CPU or O.C.ing higher if you can.BF3 is very CPU demanding and it requires a very fast quad core CPU.I upgraded from 4GB to 8GB of RAM and I don't notice any difference.I've never seen the RAM usage go above 3GB so I think you will be fine at 4GB for now.

What is the make/model of your PSU?

I have a Corsair AX850 Professional Gold series. Pretty high-end. 😛

 

[purple stain]

Yes it is.

 

[cuecuemore]

Shouldn't be a big deal. Check this out for reference:
http://www.techpowerup.com/reviews/AMD/HD_5870_PCI-Express_Scaling/1.html