Graphics upgrade?

[HKH]

Hi I kinda need some suggestions
First off here is my rig:

AMD 955BE c2 stepping
MSI 790GX-GD65
2x 5850 in crossfire config
750w PSU
I run my games at 1920x1080

I currently have my 955BE overclocked to 3.7ghz (freaking c2 stepping BSODs when I get to 3.8, even with around 1.5v)

The mobo runs xfire at x8/x8

so the question is, I'm currently not satisfied with my gaming performances (yes I know the rig is powerful, but I'm not satisfied cause I can't run everything maxed.....)

1) How much performance would I gain if I switched to 790FX x16/x16 xfire?
2) Is my CPU bottlenecking my GPUs, will the performance be better if I get an Intel i7 930 and overclock it over 4ghz?
3) Should I rather get a 790FX and buy another 5850 to tri-fire it? (I would need to buy a new PSU)
4) I can't get my cards to run at 850/1200 stable, max stable I can get it 825/1175, should I temper with the voltage?
5) Should I wait for fermi and swap the 2 5850s for a fermi? (Probably gotta wait for benches to come out)

So which of the following should I consider?

So here are my choices atm:
1) Buy a 790FX motherboard
2) Buy a 790FX motherboard+ another 5850 + a new PSU
3) Buy a x58 motherboard + i7 930
4) Buy a x58 motherboard +i7 930 + another 5850 + a new PSU (kinda expensive I prolly wouldn't "really" consider it)
5) Swap my 2 5850s for a 5970
6) Wait for 890FX and upgrade then
7) Wait for Fermi and upgrade if it beats 2 5850s in xfire at benchmarks

P.S: I don't want to spend too much money

Thank you for your attention

 

[requiemsallure]

1. about 4-7%
2. i couldn't imagine that your CPU would be bottlenecking your GPU's, but yes the i7-930 is much more powerful when overclocked
3. to answer this question what are you trying to max out that you cannot already?
4. which 5850's do you have (Manufacturer)
5. yes wait for the benchmarks to come out. if you end up doing this i would be interested in buying a 5850

wait for Fermi, anyway, if not for the cards, ATI's card prices might drop and your options might be re-prioritized

 

[megamanx00]

Yup, your probably CPU turtlenecked in most situations. As for your CPU, it will BSOD or cause the system to restart if it get's too hot. If you're using the stock cooler then you need to upgrade your cooler to push for more. Of course, even if you get your CPU up to 4.0GHz the improvement won't be huge. Same goes for switching to a 790FX board, the extra bandwidth will help for GPU to GPU communication, but it won't be a big difference, unless you're using eyeinfinity. I understand that eyeinfinity is more demanding on the PCI-E bandwidth in crossfire and that is why it was not initially allowed with crossfire in the launch drivers.

Anyway, if you want a sizeable increase, go with an i7-920 or 930 and a good X58 board, a good aftermarket cooler, and overclock it to 4.0Ghz or so.

 

[megamanx00]

I just want to add that I'm more than happy with my single 5870 and I think you're crazy ^_^.