HIS 5850 Unstable above/below 775/600 @ 1.088v

[mmartoccia]

Any ideas why I cannot OC this card?  I'm get a steady 316MHs with the current settings but feel I am underutilizing this card.  If I adjust the core speed to 774 or 776 the card stops mining.  What am I doing wrong?

[ssateneth]

Any ideas why I cannot OC this card?  I'm get a steady 316MHs with the current settings but feel I am underutilizing this card.  If I adjust the core speed to 774 or 776 the card stops mining.  What am I doing wrong?

600MHZ ram speed generally isn't stable. You'll have to try about 800+ or sub-350. There are certain straps where memory will jump to a different timing; the higher the mhz the higher (looser) the timing, but it only changes at a certain threshhold. 600mhz is probably close to a threshhold (timings are too tight) and not stable at that frequency.

Also I found if you are going to change clocks on the fly, make sure there isn't a significant load (mining) on the video card, or it can cause bad problems.

[mmartoccia]

Thanks ssateneth!  Dropping the mem to 300 worked! I am now able to clock the core up to 970 (60c) on one card and 870 (63c) on the other.  One thing I noticed as well is that the cards are stable at v 1.088 and I had to set this v for all three profiles (0,1,2).  To push the cards harder, what do you think is the best way to approach this?  Raise/lower the mem or increase the voltages slightly?