Hello kingkung;
Please provide more specific details on the parts you do have. Especially;
Resolution of monitor (need to match the video card to the resolution)
Power supply (will the PSU provide enough power for the new CPU and video card)
Case (with the case hold a new, large video card and will it keep the new parts cool?)
CD ROM; (CD ROM only? Not DVD or CD burner? If not than a new DVD burner is a good idea - many games come on DVDs these days).
the resolution on my monitor is 21" 1680 x 1050
my power supply coolmaster 460watt.
i am using an old case, raidmax x1 mid gaming tower
and its a dvd burn dvd rom.
I also found a 2 Geforce 7900GS graphics card laying around from my old SLi set up. Are these Graphics cards worth using again in the new system? Or are they too old?
will that motherboard u listed support overclocks and/or unlocks of 4th core? if not i would sacrifice some gpu power for a better mobo.
Can you get the exact model of your CM 460w PSU? How old is it? It's right on the edge of what a card like the HD 6870 needs. The basic requirement is 500 Watt or greater power supply with 2 x 6 Pin PCI-e power connectors.
It looks like the HD 6870 might fit OK into your case. But you should measure carefully to make sure a 10.5" card will fit.
If not, the HD 6850 is good option for a 1680x1080 monitor.
2x Geforce 7900GS in SLI isn't a very attractive option.
You'd need a whole other motherboard choice and the cards together, have less gaming power than even a $100 graphics card today.
i actually got a new case(coolmaster HAF 922) and a new PSU(Antech Neo eco 520watt). I also found a good deal on a MOBO(Asus M4A79XTD EVO). I am going to also get that XFX 6870 u listed above: http://www.newegg.com/Product/Product.aspx?Item=N82E16814150521
is that power supply good enough to power the system if i don't go "Crossfire Setup"?
i actually got a new case(coolmaster HAF 922) and a new PSU(Antech Neo eco 520watt). I also found a good deal on a MOBO(Asus M4A79XTD EVO). I am going to also get that XFX 6870 u listed above: http://www.newegg.com/Product/Product.aspx?Item=N82E16814150521
is that power supply good enough to power the system if i don't go "Crossfire Setup"?
Err IIRC in my vault of stats, facts and benches i have data that shows 2 x 8800GTs in SLI struggling to keep up with a GTX 260 so just one GTX 460/HD 6850 will be a monumental upgrade...and GF7950 is soundly spanked by 8800GT hehe