Mining causes restart - PSU problem?

[pontiacg5]

Hello!

I have 4 7970 ghz editions on a gigabyte g1.sniper 3. Everything worked fine for some time, but now every time I try to start cgminer my system restarts.

So, first off I removed some cards. Two will work, but three or more are no good. All appear to be just fine on their own, so I'm not sure any cards are bad. I've moved them around the 4 pci-e 8/16x slots and they will work in any slot, so I don't think my mobo is bad.

My motherboard is specifically designed to run 4 cards and I'm doing so without risers (I would not advise this.) Powered risers are not needed, my board has a sata input specifically for externally powering the pci-e rails.

My power supply is a 1300W Rosewill, which I figured would be enough to run this thing. All I've got running is the cards and a sata SSD, no fans, no optical drives, nothing.

I guess I should mention that the 4 cards do just fine idling in windows, it's not until I load them up that things go south.

Anything else I should try?

Thanks for looking!

[1715486952]

1715486952

[SlyFoxy12]

I had this going on for ages, it always seems like a hardware fault but I found some important things an d it's mainly to do with overheating of the cards,

1) make sure your cards have memory underclocked, I didn't do it at first at it never worked out, constantly caused reboot not even BSODs or Kernel Panics, just plain restarts, did it and got it stable and then accidently forgot about the setting and I started getting the same reset problems.

2) really couldn't state how poor Windows can be for OpenCL, which is what graphic miners use, maybe try a linux distro, namely Xubuntu 12.04 if your going for the dedicated mining rig.

[pontiacg5]

7970's won't under clock memory that far past the engine clock unless you flash the bios. I'm not doing that, I see no need to void my warranty for that. I've run with matching engine/memory clocks since day 1 just fine? Longest uptime is over three days, the biggest problem is my shoddy network that drops and won't come back without assistance.

Can't really be cards overheating either, as they never were able to get hot. Even if I could have set the memory clock way down low it wouldn't have done any good. PC restarted before any vga activity every time. The fans would momentarily rev up, as I keep them at 100%, that was about it...

This is the first I'm hearing about windows being poor for openCL. I get a religious 700mh/s from the free air card at 1150/1150, and I can get the rest to 1150/1150 with some ridiculous box fan placement. Would Linux do better?


Anyway, I drove to microcenter and bought the most ridiculous power supply I've ever seen. It's an evga nex1500, and I am successfully back up and mining like usual. As always, newegg's house brand lets me down. This will be the last time for that!