Crossfire mobo for r600 parts

[mason.kramer]

It seems like there is a big problem for those who are considering setting up a new rig using two r600's in crossfire: As far as I can tell, there is no motherboard which supports an LGA775 socket, AND crossfire in dual PCIe x16 mode. Sure, lots of boards have two x16 slots, but when you run radeons in xfire mode on those parts, the channels only operate at x8. But we know from Tom's Hardware that even current generation video cards benefit from the full x16 bandwidth. How much more true will that be in the r600?

Is there some reason why running the cards in crossfire would mean that less bandwidth is required from each card? It seems like if this technology is really to have a benefit, it would have to get the full use out of each card....
edit: However, I do understand that the information passing from the CPU to the card is only the instructions for what to render, and the size of those instructions (theoretically) do not increase just because you have two GPUs. So perhaps one x16 is sufficient to communicate all of the CPU's instructions and there is no bottleneck, regardless of whether those instructions are getting passed via two x8 channels or via one x16 channel. Is that logical?

edit: And can we expect a chipset that supports true dual x16 crossfire?

 

[InorganicMatter]

Badaxe 2?

 

[R1ckCa1n]

Who said you need two 16x PCI-e slots for crossfire? The RD600 is only two 8x PCI-e slots. I would say most 975 chipsets will have no problem and some 965 chipsets should work (given they work for X1900 crossfire right now).

 

[mason.kramer]

Who said you need two 16x PCI-e slots for crossfire?

But we know from Tom's Hardware that even current generation video cards benefit from the full x16 bandwidth

...I know they will function in a 975 board, but will they be interface bottlenecked?

 

[Sizzy]

Perharps its time to consider going AMD all the way (cpu, motherboard + GPU) . Personally, I am considering the MSI K9A for my next build. If the rumour about Barcelona performance is true, it will be a treat.

 

[mason.kramer]

Will Barcelonas fit into the current mobos?

 

[InorganicMatter]

Perharps its time to consider going AMD all the way (cpu, motherboard + GPU) . Personally, I am considering the MSI K9A for my next build. If the rumour about Barcelona performance is true, it will be a treat.

Why pay twice to go AMD (AM2 now and Barcelona later), when you can get a Core 2 system now that is going to perform the same as Barcelona. Industry insiders at XS were saying the 42% gains were BS a while ago, and the real numbers were actually less than 10%. Doesn't make sense to pay extra for that.

 

[Sizzy]

Why pay twice to go AMD (AM2 now and Barcelona later), when you can get a Core 2 system now that is going to perform the same as Barcelona.

Partly because the OP is looking for true dual x16 Crossfire setup. None is available right now for C2D platform. Hence I suggest the AM2 platform. Having the option to upgrade to Barcelona later on is a nice bonus.

Industry insiders at XS were saying the 42% gains were BS a while ago, and the real numbers were actually less than 10%. Doesn't make sense to pay extra for that.

Maybe not just a rumour anymore ...

AMD also disclosed updated performance projections for its upcoming native Quad-Core AMD Opteron™ processors, code-named ‘Barcelona.’ The new Barcelona projections are based on the latest SPECcpu2006 benchmarks and show that AMD expects to have up to a 50 percent advantage in floating point performance and 20 percent in integer performance over the competition’s highest-performing quad-core processor at the same frequency.

AMD Press Release