I currently have 1 stick of pc3200 corsair ram. I am building a computer for a friend that does not overclock, and for his computer I have two sticks of some pc3200 ram (i'd have to go look to get more specific). My question is as follows:

He won't notice the difference between the two RAM options, but I am trying to get into overclocking and would like to keep the best of the two. Is there a relativley quick (The computer goes to him tommorrow, but I can stay up really late ) way to determine which ram I should go with? Also (this is a real n00b question), can you run dual channel with any two identical sticks? Does dual channel always out-perform a single stick? Please help me decide, I don't have much time.

You could try a quick-and-dirty test regimen to see which gives out first. Don't adjust timings or voltages or anything, just try at clocks of 200-205-210-215-... and see which one starts barfing first in memtest86 when tested individually.

I'm not sure how exact the match has to be... in one situation I tried to run a pair of old DDR266 sticks together in dual-channel... one with Micron chips and one with Samsung, and it ran as well as could be expected given the system had a flaky PSU at the time (I was using it to substitute for some DDR400 I blamed for the problem)

I'd expect dual-channel to be more bandwidth, but more sensitive to FSB runup and instability (please feel free to correct me).

I just pulled the ram out of this computer and it is 2x Corsair XMS memory with heatspreaders. I think mine is Corsair ValueSelect, so right now i'm leaning towards the pair of 512 sticks.

edit - Ok so here's the lowdown

My current ram:
Corsair PC3200 Value Select (1x 1GB)
Timing: 3-3-3-7

New stuff:
Corsair PC3200 XMS (2x 512MB)
Timing: 2-3-3-6

I think it's pretty obvious that I want the new stuff right? I'm putting in my computer right now, but I still have tommorrow before late night to change my mind. A couple "duh" responses would be nice