Claymore miner reporting incorrect shares on 2nd hand GPU - unoverclock??

[Roaders]

Hi All

I bought a second hand GTX 1070 and when running in claymore miner I get this error:

GPU #7 got incorrect share. If you see this warning often, make sure you did not overclock it too much.

I have not overclocked it but on contacting the previous owner he says that he did using MSI Afterburner.

I am currently trying to get Windows 10 working on my mining rig so that I can undo this but I am a bit unsure about how this works.

Am I correct in thinking that overclocking does not actually save anything to the card? If this is the case then any settings the previous owner applied will not be on the card.

Does anyone have any suggestions as to how I can fix this issue?

In a related question I was hoping to apply overclocking settings to the cards in windows and then re-boot into linux and have the cards run using those settings. Is this possible?

Thanks

[os2sam]

https://bitcointalk.org/index.php?topic=556244.msg6060876#msg6060876

[Za1n]

Are you seeing the error message all the time or just once in awhile? It is normal to see it occasionally (once every few hours), but if it is showing up all the time yes you do have an problem.

You are correct in thinking that any overclocking settings the previous owner applied by MSI Afterburner will not carry over with the card to a new machine. It will also not carry over from Windows to Linux.

It is possible however the previous owner did try to mess with the card's BIOS or maybe he even pushed it too hard and caused some damage that only crops up when mining.

I think the simplest solution is to install Windows and download MSI Afterbuner yourself and try to play around with the settings a bit. Usually people will reduce the power limit some, maybe try 85% to start and then depending on the algorithm you are mining adjust the core and memory clocks. For Ethereum you can actually lower the core about 100 MHz and increase the memory to 300-400 to start. If it stabilizes you can try pushing it harder. For Zcash the opposite is true, you could leave the memory clocks at 0 or even reduce them a bit -300 and increase the core clock a little at first, maybe start with +100.

If that works you will know it is not an issue with the card itself and you can go back to Linux and try to apply the settings via the Claymore command line

If no matter what you try you continue to get the error, the card may have been damaged somehow and you will need to either return it to the person you bought it from or try for a RMA with the manufacturer.