HASH rate not as expected

[tommywommy]

Hi, I'm running 2x5850 vapor-x (obviously not in CF). Using GUIMiner. My hash rate is combined 400 MHash/s (204MHash each). Isn't this a little on the low side? Table (https://en.bitcoin.it/wiki/Mining_hardware_comparison) reads 270 at least (and mine is factory overclocked). I've not OC past factory, so why is this low?

If it helps my proc is q6700 @ 2.66, my environment is windows 8.

Any suggestions?


P.S: Unrelated, but my MHASH dropped to ~ 400KHash/s and I had to restart the miners. Any idea why this happened? I'm leaving my system on tonight, hope it doesn't drop while I'm sleeping.
EDIT: Found this, but it's not helpful: https://bitcointalk.org/index.php?topic=145265.0
Thanks
Tom

[tommywommy]

does bumping work?

[Gator-hex]

Use catalyst 12.11beta drivers from you cards manufacturer, disable crossfire, and overclock using catalyst overdrive.

I recommend mining on 50BTC or BitMinter pools.

I get 260MH/s on 5830s you should be beating that.

[tommywommy]

that 260 hash is on OC?

[Gator-hex]

Yeah, just a slight overclock, no voltage mods or anything that could harm the cards, though some people claim to get them to 300MH/s