Bitcoin Forum

Asrock H61DEL has got 1 PCIE x16 + 5 PCIE x1.
Installed Ubuntu 12.04, plugged in 6 x 6970 and 2x1000W PSU with 3 x 8(6+2) PCIE plugs in each PSU.
Day after mining LTC, Mobo died, and now refuses to start, not working, no matter what.

So here is the question:
Which Mobo can truly handle 24h 6 GPU load?

Any 6x PCIe board with powered risers...

http://www.reddit.com/r/litecoinmining/comments/1dvit7/the_powered_riser_problem_is_there_a_hardware/

The MSI Z77A-GD55 is supposed to handle 6 gpus without any problems.
The MSI Z77A-GD65 is confirmed by many to handle 7 gpus without any problems.

The MSI Z77A-G45 is confirmed by many to handle 6 GPUs if you do a presence pin short on slot number 5 which takes all of a few minutes.  Slot number 4 must be left empty as it becomes auto disabled.

Power efficient Ivy Bridge Celeron G1610's can be dropped in and had on amazon for $43 bucks.
http://www.amazon.com/Intel-Celeron-2-60GHz-Processor-BX80637G1610/dp/B00B4BJYVU

Thread for 6-7 gpu mobos;
https://bitcointalk.org/index.php?topic=186877.0

Thread for 6 gpu's in Win8;
https://bitcointalk.org/index.php?topic=193695.0

Thread for presence pin shorting;
https://bitcointalk.org/index.php?topic=102547
https://bitcointalk.org/index.php?topic=36061.0

I personally have the MSI Z77A-G45 with the presence pin short and it has been rocking away with 6 7970s 24/7. I'm using powered risers which I highly recommend as it takes the power load off of the motherboard.  My 6 GPUs without powered risers were drawing 250watts+ from the mobo.  Any next builds I do though will be with the GD65 and put 7 GPUs on Linux. Definitely worth the few extra bucks for the ability of adding the 7th gpu. :)

Thread for making powered risers;
https://bitcointalk.org/index.php?topic=76121.0

I bought this :

http://www.evga.com/Products/Product.aspx?pn=270-WS-W555-A2

Isn't cheap.

That's why you need to use powered risers!
PM me if you need any.

does the MSI Z77A-G45 still require pin short with sandy bridge processor?

Yes^  I'm using ivy bridge processor and still needed the pin short.  It's very simple and easy to do though.  Worth doing if you have the board already.  If buying a new board I'd go for the GD55 or GD65

I got 5 running on my GA-FX990-UD5, 6 Im sure will need PCIe slots shorted. The UD5 was only 100.00 bones.  :P

MSI Z77A-G45/G55. Can handle 5 cards, 6 with an extremely trivial presence short on the middle pci-e 16x, takes not even 5 minutes.

MSI Z77A-GD65 can supposedly support 7 cards. No idea if any slots require shorting.

Have an MSI that can handle 6 X if you are interested.

I have the GIGABYTE 990XA-UD7 its a very nice board will handle 6 gpus running @ 4x and a pci card. I think your problem here is you are using two power supply. Computer power supply have to be rated specifically to be uses in pairs. There has to be internal isolation between rails and grounds otherwise you can get up to 24v on a rail. Thats most likely why it died. Modern graphics cards only pull signal voltages off the cards. There is not enough current draw though the board to kill it, its the voltage. The reason risers work is when somebody uses power risers it usually power by the same supply. Also if you do not provide enough power under voltage can kill a card or motherboard as well.

Asus P8B WS does.  4 16x slots properly spaced, plus two 1x slots.  Proper C206 chipet, too.  The P8C WS is better (C216 chipset) but I've never seen one in the wild.

I run a P8B WS.  Solid as a rock.

Nice mobo that EVGA Z87 FTW.

Since you rezzed this old thread, I thought I'd bring this part up.

I'm using those PCIe USB powered risers. I have multiple setups where a riser is being powered from a different PSU than what is powering the GPU itself.

We're using Rosewill Capstone 750W Modular 80Plus GOLD. Every rig has two of the same PSU.

So how are our rigs still working just fine, if you're saying this could cause problems?

Also, how on earth could we end up with 24V on a rail, coursing through the GPU? Or the motherboard for that matter? If we were to somehow get a 24V draw, something else would be wrong than the inherent design of the rig, and I doubt we would even be mining right now.

I'm legitimately curious, as I know a lot of people run multiple GPUs per rig, and we're doing it on multiple rigs with no issues. Is it because they're the same make/model of PSU that it's fine?

If I have mobo that supports 7 gpus can I combine two psus to work with my graphic cards? Do I have to have the same model of graphic cards to mine LTC?