Upgrade advice question d to q

[Spirals]

Hey,
I have a few questions about doing an upgrade, and have decided what I Dont want to do (i7). I have an d8400 that is running really well on water. 4.05ghz like a rock.
I am looking at the prices sloowwwlly falling on the q9550 and I am thinking of pulling the trigger. I have a solid gigabyte board that is upgraded to run the 45nm so that shouldnt be a problem.
I am aware that I probably wont see 4 ghz on a quad, and that does seem wierd to downgrade clock speed.
I am running xp32, but plan to go to 64bit. Mostly because of having 8 gigs of ram in this pc.
I only run games and benchmarks. Thats my whole deal when it comes to pcs heh.
Will I see much improvement from the 8400 to the 9550?
Should I switch to xp64 bit with this rig?
Oh btw I run a 4870 for vid.
Thanks for any advice.

 

[Lamont Cranston]

i hate to say it but if you arent going i7 then i would hold off.....most apps dont take real advantage of quad core anyhow so you probably would notice a huge difference....on the ram side though i went from 4 to 8 gig and thus a switch to a 64 bit os and it has a much faster feel to it.... just my .02