5830 getting very poor performance

[Jigsaw]

Hi there,

I recently acquired 4 brand new 5830s for $320 so I put them into a spare setup I had. Upon installing Win7, AMD CCC, .NET4, MSI Afterburner, and poclmbm I started all 4 miners. According to the bitcoin wiki the 5830s were getting between 280-320 MH/s, but I'm only hitting 170 on stock settings and 190 with 900/500 overclocks. Am I missing something blatantly obvious or is something wrong. I'm attaching some pics of the setup. If there's any information you need I'd be happy to provide it.

Thanks.

P.S. While I was writing this, three out the 4 miners dropped to 300-400 khash/s, restarting them made them work at 190mh/s again. Any reason for that?

[Jigsaw]

Now the rate has dropped to 300 kh/s for each GPU and GPU load is 0%
WTF is going on?
Power usage has dropped to 250W for entire rig.

[KWH]

I believe my settings were 800/800 Intensity 16. That got me just under 500kh/s for the pair.
Edit: I was using cgminer.

You've checked the usual things such as screensaver, power profiles? Up the Mem speed a bit, see what happens. I had a GPU that wouldn't work but 100 Mhz below stock.

[Jigsaw]

Will try that. And i'm guessing you meant 500 MH/s not KH/s.

[KWH]

Will try that. And i'm guessing you meant 500 MH/s not KH/s.

For BTC yes but I've been LTC mining for awhile since it's not worth it for BTC, so kh/s.

[LinkLad13]

I had a similar problem so i switched to Linuxcoin used the same settings and got around 310 MH/s. I think that linux distribution is outdated now but its worth a try