motherboards

[ilovebarny]

Hi folks.

need some advice. i was thinking about upgrading my graphics card from an nvidia 8600gt to a radion 4850 or 4870. but i dont think my BFG 680i sli mobo is pci-e 2.0 16x. it doesn't say in my manual. so what i need to know is if my mother board is 2.00 compatable and if not what mobo should i upgrade to. i would like to stick to $180 dollers or less for a mobo that is crossfireable. and i would like to keep my processor( a E6750).

any suggestions?

 

[dagger]

PCIE2.0 is backward compatible. The card will run on your old motherboard. Not sure if there'll be any bottlenecking due to slower pcie bus.

For crossfire, you need either x38 or x48 motherboards.

 

[outlw6669]

Yeah, PICe 2.0 is backward compatiable.
The x38/x48 is a good chipset but you may want to check out the newer P45. A little more energy efficient, a lot more overclockable at the expense of some PCIe bandwidth. With this chipset you have the option to tipple CrossFire in 8x PCIe2, 8x PCIe2, 4x PCIe1 mode. Not that it is really a disadvantage, PCIe2 @ 8x is just as fast as PCIe1 @ 16x.

 

[ilovebarny]

oh ok cool then ill probably keep my board cause i just got it for christmas and it has been rock soiled for me. sweet. the 4850( or 4870 ) will blow my card out of the water. thanks for the post dagger.

 

[dagger]

Not that it is really a disadvantage, PCIe2 @ 8x is just as fast as PCIe1 @ 16x.

That is wrong. 4850 is already fast enough to be severely bottlenecked by it.
http://www.tweaktown.com/articles/1472/7/page_7_benchmarks_crysis/index.html

 

[outlw6669]

That is wrong. 4850 is already fast enough to be severely bottlenecked by it.
http://www.tweaktown.com/articles/1472/7/page_7_benchmarks_crysis/index.html

Hrm.
Thats interesting.
I was going off the results from toms test Here.
Specifically the 9800GX2 tests where it shows a minimal performance drop between PCIe2 16x and 8x.
As the GX2 still puts more power thru a single slot than a 48xx I assumed there would be no or a minimal drop in performance.
Very interesting indeed...

 

[ilovebarny]

wow ya that is interesting. maybe it has to do with the drivers? thanks so much for the help guys.

 

[pcgamer12]

daggers point is dumb. the guy has an sli board, the bottlenecking is from cf. assuming he doesnt cf, he cant. the bottlenecking will be halved and gone.

 

[pcgamer12]

show some links to bottlenecking in single mode.

 

[outlw6669]

show some links to bottlenecking in single mode.

Just to show ya it can be done

 

[smotman]

am i missing something ? Isnt the asus p5q pro p45 board capable of cf at x16 ?

 

[outlw6669]

am i missing something ? Isnt the asus p5q pro p45 board capable of cf at x16 ?

Yes and no.
The P45 chipset only has 16 PCIe 2.0 lanes dedicated to graphics.
For CrossFire it is split 8x and 8x PCIe 2.0.
Because PCIe 2 has double the bandwidth of PCIe 1, it is the same as 16x 16x PCIe 1 CrossFire.

You are probably thinking of the x48 chipset...