Did more testing again today. Great guy to work with. Prompt payment again.

Ive tried them all I think. On a 5850, but I suspect the results apply equally to a 5830. CGminer is fastest. Bitminter is very close. Close enough that I probably wouldnt care. If you want a nice looking flashy GUI miner that launches from a website,  go bitminter. If you prefer a more powerful CLI app, with pool failover, fan control and everything, cgminer is it. No need to look elsewhere.

If your card is still covered by warranty for a long time to come (and you think you can get away with voiding it), well, even then probably not. Depends on your luck on how much of an increase the overvolt nets you. Keep in mind it may take weeks before you get an RMA, thats a lot of lost revenue to make up with slightly higher hash rates.

At least if you do want to overvolt, do minor increases and keep your temps low, not 80+C. I killed a 5850 by accidentally overvolting it through the roof and hitting the thermal throttles of 100C GPU and 130VRM. It took about 30 minutes to kill it dead. Heat is bad, overvolt is bad, the combination is stupid.

Overvolting isnt smart. Not only is it even more likely to cause premature failures than overheating (and the combination is pretty much a guaranteed premature dead, again google electromigration), it doesnt make economic sense either.

Power consumption increases exponentially with voltage, your hashrate does not, and will only increase marginally with increased voltage. Since power is the biggest cost for most people, it will make more sense to undervolt than overvolt as it can (greatly) improve your hashrate/W.

Unless you steal electricity of course.

There isnt. Not all cards support it. Yours doesnt. In fact, most non reference cards dont support it, but AFAICT, most non reference cards also have no VRM temperature problem.

Learn to use cgminer. It will auto overclock (and reduce clocks if needed) and even restart the GPU's if they crash. That doesnt always work, but usually it does. It will also take care of adjusting the fan speed. Your temps are great, feel free to use the autofan option and set the target temperature a bit higher than what you have now, so it doesnt sound like a hairdryer. Do check your VRM temps with gpu-z though, just to be sure they arent burning up while the GPU itself is nice and cool.

Drop the intensity to 6, if you get a bit of judder still in movies/games, drop it to 5. Use the affinity to put cgminer on 1 core but it is a sempron, may need go to I4 but you should get a fully usable system with good mining performance, It basically uses whats available at them intensitys and lets your system roll on

no need, 85% with them temps is sweet

As long as your temps are below 90 put your fans on 100%, auto IS A BAD IDEA, ALWAYS. Ive seen mine throttle the fan down when its 100% workload because of all sorts of things. Hense why i have 6 series cards on some cause my 5 series fans failed due to this. 6 series sucks compared to 5

I always have 100% and as long as it doesnt get too hot, 100+ degrees they WILL seize up. Then again, i plan to replace cards every year or 2 so its not as if im too fussed about thrashing the fans. I wouldn't go below 85% fan speed, Dependant on your location as well though (tempreture outside).

Looks like you got it working sweet. Try playing around a little, you might get slighly different results with say 2 threads, not 4. Worksize 128, not 256 etc etc but Vectors 2 seems to be the best on all of mine. Everyones system behaves differently, cause no card/board is the same