8x+8x crossfire vs 16x+16x

redwave3099

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how much of a performance diff is there really between going 8x crossfire instead 16x. would it be a waste to by a mob that supports only 8x crossfire nowadays?
 

JDocs

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Depends heavily on the cards and games involved. But even dual 4870 would be quite happy (and so minimal performance degradation) on x8/x8.
 

kyeana

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probably wouldn't make more then a 5% difference, if that depending on the game etc. If money is a concern just go with the x8x8 and dont worry about the x48 mobo's. It should still run like a champ
 

Zecow

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depends on the resolution. under 1900x1200 not much of a difference as theres enough bandwidth on the bus and at that resolution, it relies more on CPU. At 1900x1200, this is where the GPU comes into play - difference of a few frames - I'd say 10-15%. Above 1900x1200, it takes quite a hit, as it requires as much bandwidth as possible.
 

spathotan

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At 1680 x 1050 an 8x/8x solution for say... 4850's, 9800GTX, 8800GT is just fine. But if youre gonna be using 4870's then you should probably look into an X48.
 

3Ball

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There wont be to large of a difference. I personally just ordered a ASUS P5Q Pro, so that I can reuse my memory and drop in a Q9550 around x-mas time with the ability to go crossfire if need be. I am not to worried about the performance difference. I think it will be fine. In most cases unnoticeable unless like others have said...at very high resolutions. I play at 1680x1050 and will never go higher than 1920x1200 if I so choose to upgrade my monitor. imo its not worth the price premium for the X48, but to each his own.

Best,

3Ball
 

redwave3099

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well I have AMD processor and I play at 1680x1050, the cards in question are a 4850 and a 4870 (got it cheap) was looking at this:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157139 primary (same chip set I am using atm) or

http://www.newegg.com/Product/Product.aspx?Item=N82E16813157141

or to spend more possibly these:

http://www.newegg.com/Product/Product.aspx?Item=N82E16813136044

http://www.newegg.com/Product/Product.aspx?Item=N82E16813136057

http://www.newegg.com/Product/Product.aspx?Item=N82E16813130136

also need a new power supply....prob easier to get a 4870x2 or 4850x2 lol
 
At moderate resolutions (up to 1920x1200) there will be a minimal performance drop when you use PCIe 2.0 8x Crossfire vs 16x. Above that, you will begin to run into some bandwidth limitations.

Take a look at This Crossfire Chipset Comparison for some good comparative benchmarks.
Personally, on a budget, I would say an Intel P45 based motherboard would be a great choice.

Edit (w00t, I can edit my posts again!):
Just saw you already have an AMD CPU.
In that case, I would agree that a 790GX with the SB750 would work great for you.



------
Obama FTW!
 

bobbknight

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I could not wait for the DFI atx size board to come out so I went with the MSI.
It works great.
I stay away from Asus and by extension Asrock they have the worst RMA customer service. I took them 6 months to get a good board back in my hands, after 5 tries.
So I will not buy anything from Asus.
 

spathotan

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Ahh ok, youre using AMD. In that case I susgest the same as others have, 790GX or 790FX with the 750 Southbridge. Definetly stick with those.
 

3Ball

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Yea thats my bad for assuming Intel before we knew what he was runnin. Shoulda asked I suppose.

Best,

3Ball