Need AMD Crossfire help!

[Brianpilotdude]

Hey Guys,

I have 2 HIS Radeon HD6790 GPUs and I would like to run crossfire. The problem I am running into is my motherboard's (Asus Sabertooth X58) PCI Express slots are to close together and because of the cooling, the top card runs WAY to hot. My other problem is when I crossfire the cards, I can't hardly see an increase in performance. For instance, I use a GUIMINER bitcoin miner and when I use 1 card I get about 215.0 MH/s and when I crossfire the cards, this number hardly increases, when it should double according to the numbers.

What I am here to ask is, for the cooling, how can I solve this? Is a new motherboard the way to go? If so, which one? I have noticed the a lack if X58 motherboards on the market and the ones that I find are either $100 and too cheap or pushing $400-$500. I can't figure it out..

And what might I look into with optimizing my Crossfire performance?

Thank you in advance
Brian

My Setup
Antec 1200
Intel Core i7 920 4.0GHz
Asus Sabertooth X58
Antec Kuhler 920
HIS Radeon HD6790
Kingwin 1000watt PSU
HITACHI 750GB 7200RPM
Corsair Vengance 8gb DDR3
Creative Sound Blaster Fatal1ty Recon 3D

 

[Kougar]

I can't speak for Bitcoin mining as I know very little about it, but keep in mind Crossfiring the cards is primarily done for games and graphics rendering. For example, if you are folding Crossfiring the cards would not affect anything because computational work likely doesn't use the graphics rendering side of the drivers/hardware.

From what I can tell by googling, Crossfire mode does nothing for the bitcoin client. Most users just run the bitcoin client both cards with Crossfire disabled and are claiming better performance. Folding@home is the same way with NVIDIA hardware as it doesn't require SLI or make use of it to run on multiple cards. You would need to research how to properly set up your bitcoin client if it isn't already utilizing both GPUs.

X58 is really old hardware, and that is why you're having trouble. X58 launched in 2008 so most of it is gonna be used stuff by now. X79 and LGA2011 processors are what replaced it.

You might try using the lowest PCIe slot on your motherboard. Even though it is only x4 speed, it may provide enough bandwidth to not affect bitcoin mining performance.

 

[Brianpilotdude]

I can't speak for Bitcoin mining as I know very little about it, but keep in mind Crossfiring the cards is primarily done for games and graphics rendering. For example, if you are folding Crossfiring the cards would not affect anything because computational work likely doesn't use the graphics rendering side of the drivers/hardware.

From what I can tell by googling, Crossfire mode does nothing for the bitcoin client. Most users just run the bitcoin client both cards with Crossfire disabled and are claiming better performance. Folding@home is the same way with NVIDIA hardware as it doesn't require SLI or make use of it to run on multiple cards. You would need to research how to properly set up your bitcoin client if it isn't already utilizing both GPUs.

X58 is really old hardware, and that is why you're having trouble. X58 launched in 2008 so most of it is gonna be used stuff by now. X79 and LGA2011 processors are what replaced it.

You might try using the lowest PCIe slot on your motherboard. Even though it is only x4 speed, it may provide enough bandwidth to not affect bitcoin mining performance.

Really? I know many people with large Bitcoin mining rigs run multiple cards, but i'm not sure if they actually have them crossfired or SLI, but I know it increases performance, which I am not getting. Guiminer does not utilize both cards at the same time, so maybe I should try to create a second worker or another client of it to use the 2nd card, but from what you're telling me, it all makes sense.

I would love to upgrade to LGA 2011, but I simply don't have the money for another processor and motherboard for my system, at least I don't think. I need to look into it. I found an X58 mobo that might work ( http://www.amazon.com/EVGA-CrossFireX-USB3-0-Motherboard-132-GT-E768-TR/dp/B003NE5JLK/ref=pd_cp_e_2 ) any opinions?

Thanks
Brian

 

[Kougar]

Again, I suggest you check the bitcoin forums. All the posts I've seen are like these:

http://bitcoin.stackexchange.com/qu...-in-crossfire-or-with-2-pcs-with-one-gpu-each

https://bitcointalk.org/index.php?topic=10714.0

Folding@home is similar... one client worker per GPU. Crossfire doesn't affect anything.

That EVGA motherboard looks fine, but if you can get both of your GPUs running I would still suggest you test out the bottom PCIe slot in your motherboard. Since most of the data is self-contained in the GPU while it mines, it probably won't need the missing bandwidth.