thanks for the reply i did try i13 with someone elses settings did work as well for me im getting a stable 1300 1350 from the good cards @ i20

my current settings

color 03

bfgminer --scrypt --temp-cutoff 98 --url=stratum+tcp://litecoinpool.org:3333 --userpass= --url=stratum+tcp://us.litecoinpool.org:3333 --userpass= --failover-only --thread-concurrency=24000 --intensity=20



ive not dropped the freq of the card but am running at 1160mv stable for heat i cant keep my loop cool enough without undervolting and if your looking at my setup and seeing bfgminer ive also tried cgminer 3.1.0 and 3.3.0 but cgminer wont read temps at all and bfgminer shows me temps but they dont match the cards as in they are the right temps but in the wrong order

well thought id add my progress in trying to solve this, i have now cleaned up the cores and repasted using arctic silver 4, and have replaced all the thermal pads,

its amazing the difference new paste and pads on a clean surface helps its now the coolest card in my water loop even after another card the same has used the water first, my temps have dropped by 10c easy under load.

unfortunatly it hasnt fixed my issue, BUT for stability i was playing around with just using one side of the card or the other to see witch it was, now i can run the one half full speed ahead and its stable but the other side will run for about 5 mins on i20 and upto 3 hours on i12.

one thing i might try is running the one core thats bad on its own in my water loop so it doesnt get hot and see if it is caused by heat, my way of thinking here is if ive damaged the VRM chip on my board it might work fine untill it hits this temp, in witch case i should be able to see about getting that chip replaced.

thoughts anyone does that sound right to you guys?

ive been having the same problem with one of my cards im running to psus

1 ax1200i that power mobo cpu 1hdd and 2 7990's the "i" part of the psu allows me to see how much they are drawing well under

i also have a cx750 running 1 7990 thats the one thats been causing me issues with this 511c temp issue has anyone found a fix ive had to unplug that card, im going to redo the thermal pads and paste tomorrow and see if that helps, but if a B1tch as im running these 3 cards watercooled tis a pain breaking the loop to diagnose this card.

are we thinking this is a cgminer issue, as its still running cgminer with the other 2 cards and they run perfectly?

Many Thanks

James

Edited but, just looked at that photo put up its exactly the same card thats failing in my system too number 4, if that helps, ive switched the power for the cards around and tried running the supposed bad card on the big psu no different

hi guys new to the forum this is my first post,

i have found a thread on this forum that relates to the same issues im having, https://bitcointalk.org/index.php?topic=360964.0
that link is someone else with similar ish hardware but i cant post in that thread

i started mining about 3 months ago and have now built a custom rig to mine with

Corsair Odsidian 900D
Asrock Fatality gaming mobo
Intel Duel Core chip G620T i think,
3x Hd 7990's all malta cores, all 3 now have waterclocks, i fitted only 1 of them and thats the card im having issues with.
Corsair AX1200i
Corsair TX750 Both in use on my board 1200 = 2gpu and mobo 750 = 1 gpu
windows 8 x64
cgminer 3.7.0 and i was using 3.1.0


now for the problem, the one card that i added a waterblock too has started throwing me problems, i mined on it without issue except slightly higher temps than i would have liked mid 80s, however now i have added a water block and now run it constantly untill yesterday.

i should add to this it mined for about a week with the waterblock on i kept an eye on temps no higher than 85c on either core

my system started locking up first this one card was mining slowly no temp rise out of the ordinary, so i just left it for a bit to see if it would speed up, when i next look at the machine it had locked and frozen the picture on the screen the card in question showing something like 500c on the temp scale, everytime it locks it shows me that sort of temp.

troubleshooting steps ive taken,

updates drivers for all video cards (locks up when it gets to the card in question)
updated cgminer
tried bfgminer
run this card on its own from installing drivers to mining locks on both operations
ive tried using this card on my ax 1200 psu as this one card has had its own 750 psu to soak up still no difference, my other 2 cards are fine.

i even had a spare hdd lying around so did a fresh install just to be sure still no go, any help would be much appreciated

James