Picking brains

[Swa]

So it started to crash constantly and then would go to a blue screen reporting only one working card. I tried all cards one by one in all slots, so I can rule out motherboard, risers and cards right? But as soon as I connect them in any combination it starts to crash or slow down to one card.

I swapped out the power supply and it seems to be going ok now while swapping back the old one gives the same problem. Am I doing something wrong here or is the Corsair CX850M just rubbish? It has a 5 year warrantee and should easily handle 4x480's. I am only using 5x560's which is rated at just over half of that. It seems one pin on the PSU has baked and melted the plastic.

 

[CTBP]

So it started to crash constantly and then would go to a blue screen reporting only one working card. I tried all cards one by one in all slots, so I can rule out motherboard, risers and cards right? But as soon as I connect them in any combination it starts to crash or slow down to one card.

I swapped out the power supply and it seems to be going ok now while swapping back the old one gives the same problem. Am I doing something wrong here or is the Corsair CX850M just rubbish? It has a 5 year warrantee and should easily handle 4x480's. I am only using 5x560's which is rated at just over half of that. It seems one pin on the PSU has baked and melted the plastic.

So I had a SATA power cable melt onto my PSU, seemed like it was too much power for the cable to handle, but don't ask me how these things work or how much power they can carry, cause I have no idea, it still works and there are plenty more slots which is lucky for me.

Since then I have split the GPU's so 2 of them run off one SATA power cable instead of 4 of one as I only have 4 cards in total, as for the blue screen, I don't really know, I've had many crashes which restarted with only 1 GPU visible, which required me to install the drivers all over again. It might be a driver issue, or it might be a riser issue, try completely removing all display drivers under device manager as well as all Nvidia software and do a restart with a fresh install. It worked for me, so far everything is running smoothly.

On another note, if you are using MSI afterburner, I down clocked my GPU's to 85% any lower then that they become unstable and cause the PC to lock up, it use to happen everyday, so far it has only happened about twice in a month, I am running 4 x 1070s.

Edit: I forgot the most important part, what is your PSU rated at? Silver, Gold, Platinum?

 

[Swa]

So I had a SATA power cable melt onto my PSU, seemed like it was too much power for the cable to handle, but don't ask me how these things work or how much power they can carry, cause I have no idea, it still works and there are plenty more slots which is lucky for me.

Since then I have split the GPU's so 2 of them run off one SATA power cable instead of 4 of one as I only have 4 cards in total, as for the blue screen, I don't really know, I've had many crashes which restarted with only 1 GPU visible, which required me to install the drivers all over again. It might be a driver issue, or it might be a riser issue, try completely removing all display drivers under device manager as well as all Nvidia software and do a restart with a fresh install. It worked for me, so far everything is running smoothly.

Except that in my case it seems to be the power supply as well as it doesn't matter on which rails the cards are connected, if it's two of them at the same time it stops. I should mention the blue screen is not THE blue screen but rather the one the tv shows if it doesn't get any signal. I've now also distributed them over different rails on the new PSU and will move one to the board itself as well.

On another note, if you are using MSI afterburner, I down clocked my GPU's to 85% any lower then that they become unstable and cause the PC to lock up, it use to happen everyday, so far it has only happened about twice in a month, I am running 4 x 1070s.

How does that work? I've seen the option besides just underclocking it to also set the power usage but don't really know what that does or if it will affect hashing.

Edit: I forgot the most important part, what is your PSU rated at? Silver, Gold, Platinum?

Corsair CX850M Gold

 

[Swa]

I don't understand how with the older PSU's you could use them full power but with the new higher rated ones it wants to start to melt the moment you go over half its rating. Perhaps I'll just buy cheap 450W's for ~R500 from now on and run 2 cards on each as it seems the high wattage ones draw their power from the same source.

 

[CTBP]

You should try get a refund on that PSU, and pay in extra to get a larger one, always go much bigger than you need, I see those cards actually pull a maximum of 150W each according to Nvidia, so you are sitting at 600W total, then you still have to add your CPU, MB and Drives, you could be near the limit for that PSU. I just moved the power slider on MSI afterburner to 85%, no need to touch the other controls, it has been mostly stable since then.

 

[Swa]

You should try get a refund on that PSU, and pay in extra to get a larger one, always go much bigger than you need, I see those cards actually pull a maximum of 150W each according to Nvidia, so you are sitting at 600W total, then you still have to add your CPU, MB and Drives, you could be near the limit for that PSU. I just moved the power slider on MSI afterburner to 85%, no need to touch the other controls, it has been mostly stable since then.

The cards are listed at 60-80W. I doubt a 125MHz core overclock and a memory overclock can push them past 100W. Add the APU and laptop drive and it shouldn't be using more than 600W. But I do think there's a design flaw they don't mention in that you should evenly distribute power or at least not draw so much from the SATA cables so I will try to send it back.