890gx motherboard and crossfire

[rajiv1990]

does nt these motherboards support crossfirex at 16x.i read that both work in 8x.what is the difference if both slots support 16x.would it be better that x58 motherboards are better for gaming?

 

[Niklas_13]

16x16 VS 8x8 is a small differences about 4 to 6 %. X58 would be better if your going to run 3 GPUs, X58 would be the way to go. if its just 2 GPU under HD 5870 8x8x will be fine.

 

[Lmeow]

The 890GX chipset has one PCI-e 16x/two PCI-e 8x lanes, which do not affect performance of cards which do not need/use all of the bandwidth which the 16x PCI-e lane provides, such as the Radeon HD 5770, or GTX 260. Even cards which need a bit more bandwidth than an 8x PCI-e lane provides won't be affected too much - like niklas said, depending on the card, <10% on average, unless it's a card like the HD 4870X2 or HD 5970. In CrossFireX or SLI mode though, if one lane is 4x, (e.g. a configuration of 16x/4x or 8x/8x/4x), it will cripple most if not all multi-GPU setups.

In terms of gaming performance, AMD based 790FX or Intel based X58 or P55 w/NF200 will provide better performance than the 890GX/P55 if you use more than three or more graphics cards (if the lanes are available), or two high powered ones which need the bandwith. 790FX, X58 and P55 w/NF200 will run two, three or four cards in 16x/16x, 16x/8x/8x or 8x/8x/8x/8x mode respectively, whereas 890GX can only run in 16x/0x 8x/8x, while P55 with two PCI-e 16x lanes run in 16x/0x or 8x/8x, while P55 based boards with three lanes run in 16x/0x/4x or 8x/8x/4x.

For gaming, the CPU and graphic cards are the main factor deciding performance, unless you are using HD 4870X2s or HD 5970s in CFX, 890GX or P55 would be enough. However, do note that Phenom II X4 965s do 'bottleneck' essentially two HD 5870s in CrossFireX, even if the lanes are 16x/16x - the Core i5 750 and Core i7s fare much better, and if you are planning to CrossFireX anything more powerful than HD 5750s, I'd go for either the Core i5 750 or Core i7.

 

[Niklas_13]

The 890GX chipset has one PCI-e 16x/two PCI-e 8x lanes, which do not affect performance of cards which do not need/use all of the bandwidth which the 16x PCI-e lane provides, such as the Radeon HD 5770, or GTX 260. Even cards which need a bit more bandwidth than an 8x PCI-e lane provides won't be affected too much - like niklas said, depending on the card, <10% on average, unless it's a card like the HD 4870X2 or HD 5970. In CrossFireX or SLI mode though, if one lane is 4x, (e.g. a configuration of 16x/4x or 8x/8x/4x), it will cripple most if not all multi-GPU setups.

In terms of gaming performance, AMD based 790FX or Intel based X58 or P55 w/NF200 will provide better performance than the 890GX/P55 if you use more than three or more graphics cards (if the lanes are available), or two high powered ones which need the bandwith. 790FX, X58 and P55 w/NF200 will run two, three or four cards in 16x/16x, 16x/8x/8x or 8x/8x/8x/8x mode respectively, whereas 890GX can only run in 16x/0x 8x/8x, while P55 with two PCI-e 16x lanes run in 16x/0x or 8x/8x, while P55 based boards with three lanes run in 16x/0x/4x or 8x/8x/4x.

For gaming, the CPU and graphic cards are the main factor deciding performance, unless you are using HD 4870X2s or HD 5970s in CFX, 890GX or P55 would be enough. However, do note that Phenom II X4 965s do 'bottleneck' essentially two HD 5870s in CrossFireX, even if the lanes are 16x/16x - the Core i5 750 and Core i7s fare much better, and if you are planning to CrossFireX anything more powerful than HD 5750s, I'd go for either the Core i5 750 or Core i7.

wow nicely put

 

[rajiv1990]

The 890GX chipset has one PCI-e 16x/two PCI-e 8x lanes, which do not affect performance of cards which do not need/use all of the bandwidth which the 16x PCI-e lane provides, such as the Radeon HD 5770, or GTX 260. Even cards which need a bit more bandwidth than an 8x PCI-e lane provides won't be affected too much - like niklas said, depending on the card, <10% on average, unless it's a card like the HD 4870X2 or HD 5970. In CrossFireX or SLI mode though, if one lane is 4x, (e.g. a configuration of 16x/4x or 8x/8x/4x), it will cripple most if not all multi-GPU setups.

In terms of gaming performance, AMD based 790FX or Intel based X58 or P55 w/NF200 will provide better performance than the 890GX/P55 if you use more than three or more graphics cards (if the lanes are available), or two high powered ones which need the bandwith. 790FX, X58 and P55 w/NF200 will run two, three or four cards in 16x/16x, 16x/8x/8x or 8x/8x/8x/8x mode respectively, whereas 890GX can only run in 16x/0x 8x/8x, while P55 with two PCI-e 16x lanes run in 16x/0x or 8x/8x, while P55 based boards with three lanes run in 16x/0x/4x or 8x/8x/4x.

For gaming, the CPU and graphic cards are the main factor deciding performance, unless you are using HD 4870X2s or HD 5970s in CFX, 890GX or P55 would be enough. However, do note that Phenom II X4 965s do 'bottleneck' essentially two HD 5870s in CrossFireX, even if the lanes are 16x/16x - the Core i5 750 and Core i7s fare much better, and if you are planning to CrossFireX anything more powerful than HD 5750s, I'd go for either the Core i5 750 or Core i7.

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well you have given a clear idea about this and thank you for giving this detailed answer

But still i have one more question,

i thought that the present cpus are enough for the gaming purposes and especially those x4s but you told that
they would bottleneck.Somewhere else in some of the forum i heard that the 955 and 965 would never
be a bottle neck for gaming.Can you explain how.i thought that amd platforms with x4 are the best in economy and giving performance compared to intel.
Actually i wont go for crossfire but since you told that cpu can bottleneck the gpus,i think that will be possible in the near future as i can see technological developments in these fields
Can u suggest what platform is future proof?
i prefer amd so can u suggest best configuration with the cpus.

 

[Lmeow]

AMD Phenom II X4 955 and 965s are one of the best price performance CPUs, but only provide similar performance to Core i5 750s. In terms of future proof, socket AM3 will be compatible with Phenom II X6s, which are proposed to perform the same as Core i7s in multitasking, although worse in single-threaded applications.

 

[rajiv1990]

Best answer selected by rajiv1990.