Eah5670 three way crossfire

[wijaonka]

Okay, I have three (3) ASUS Radeon EAH5670 GPUs. It was my original intent to do a three way CrossFireX setup.

Here's the rub: According to ATis website (in micro-small type, mind you), the 5670 can only run two-way CrossFireX. According to ASUS Technical Support, the 5670 'should' be just fine running three-way.

Before I go and use the RMA I have waiting in the wings, could someone please advise as to the three-way capability of these cards?

Thank you

 

[paperfox]

I believe it depends on which 5670 manufacturer you have. I can look at newegg and see that the Sapphire version dose not have any crossfire bridge (they use sofware crossfire over the pcie slots, maybe limited to only 2 cards) while others like Asus have two bridges, which leads me to believe they can be used in 3 way crossfire.

 

[wijaonka]

See, that's what I was thinking as well (about the two visible bridges on the ASUS 5670s). My only concern is that the dual bridges are for CrossFireX, using dual interconnect cables.

Is it possible that the 5670 is 'underpowered' for three-way? The cards get their power from the PCIe slots, not from direct PSU cabling..

I think I might try the tree-way and see if I get any response, good or bad. If good, then I should be able to
run x16, x8, x8 based on my motherboard. If bad, then I'll box up the third GPU and save it for a rainy day.

Thanks. Any other input or advice or knowledge on this matter is greatly and openly welcome.

 

[lothdk]

See, that's what I was thinking as well (about the two visible bridges on the ASUS 5670s). My only concern is that the dual bridges are for CrossFireX, using dual interconnect cables.

Is it possible that the 5670 is 'underpowered' for three-way? The cards get their power from the PCIe slots, not from direct PSU cabling..

I think I might try the tree-way and see if I get any response, good or bad. If good, then I should be able to
run x16, x8, x8 based on my motherboard. If bad, then I'll box up the third GPU and save it for a rainy day.

Thanks. Any other input or advice or knowledge on this matter is greatly and openly welcome.

I have not tried running any myself, but from reading several reviews, a single 5770 is a bit faster than crossfire 5670, and more energy efficient.

Using three would be faster than a 5770, but it would depend on the game and your resolution how much more performance you would be getting.

 

[wijaonka]

Well, the whole thing is moot. As it turns out, the ASUS Rampage II Extreme motherboard is hard pressed to fit three VGAs in the appropriate PCIe slots without interfering with the onboard floppy port, fan ports, USB ports, etc. So, I'm sending card #3 back.

As I have already purchased and installed the other two cards, I'll try them out. Keep in mind, my current computer is a six-year-old Sony VAIO running Win XP 32-bit. So, even one of these 5670s should melt my face.

Thanks to all for the input, support and suggestions. I'll let you know how it all goes in a few days when the bridge interconnect cables arrive.


Here's what I'm running BTW:

ASUS EAH5670 (x2)
Enermax Galaxy EVO 1250w PSU
Intel Core i7-950 (3.06)
Corsair HX3X12G1333C9 12G 1333 DDR3
ASUS Rampage II Extreme Mobo
HP 27" Monitor
HP 21.5" Monitor
Intel 40G SSD
Western Digital 1TB HDD (x2)
Windows 7 64-Bit Ultimate
Lian Li PC-A70B Full Tower
Blu-Ray Drive
CD/DVD Drive