I have a Dual channel MoBo and I already have Corsair VS1GBKIT400 1GB Kit DDR400 PC3200 CAS2.5 and was thinking of getting a 2GB kit but I have no idea what is compatable with it.

DO you mean you have 2x512, i dont know ram serial numbers so i am not sure what you mean.

I curently have 2x512 or dc3200 400mhz and i was thinking of expanding and GETTING two 1 gb sticks but do i need non-ecc or what?

I would just get 2 more 512's you might recive a performance hit but for large landscape games you will feel a nice improvement. And i mean a performance difference of like .5 fps, depending. but i would still say that 1 gb is enough at the moment.

Well if you dont OC Coirsair's VS imo is unmatched. And most up to date mobos support dual channel and 2 1gb stick pairs... so dont worry if its up to date! As for RAM type, really, pends OCing for me. Corsair's VS 2 gb dual channel is 168: Corsair VS 2 GB Dual
Or check all 2GB dual channels on Newegg:

Newegg Ram Selections for 2GB (2X1GB)

I myself am deciding same thing.

No need to upgrade:

http://www.tomshardware.com/2005/1 [...] ally_need/

If you think your games are chopping it's probably your video card.

Hmm been all over toms hardware and other sites missed this article... test results very interesting... well, with a 7800GT and 1GB good ram, I suppose the vid card will make game much smoother and raise FPS. BF2 is interesting, people always been saying 2gb makes a huge difference. Well received, I think I myself will save 100 bucks and go a gig.

(and RAMs and easy upgrade later anyways)

The test about BF2 is a bit misleading. I've talked to the person performing the tests and it seemed they didn't got the benchmark to run at 64 player maps. When using 64 player maps and higher graphical detail BF 2 will use more than 1GB of RAM. I've seen performance gains of about 30% going from 1GB to 2GB. But BF2 is the only game I know of that takes any real advantage from 2GB of RAM.

Well I havent played BF2 anyways. Even so, Im sure it wouldnt be SO bad with 1gb and 7800gt. And dont need highest of high settings. I saw another test on legionhardware.com which showed BF2 performing better with 2 gigs like you just said. Glad clarified.

And I know certainly some MMORGs benefit. But 1gb and a great graphics card isnt like its unplayable, whats unplayable is this geforce fx 5600 and 512mb old ram. =)

The reason for BF2 being the only game to benefit is due to it's large maps, you should see some of the custom ones, you get lost. And i got a MAJOR improvement when i went from 512 to 1024 in november. I went from everything on low to all on medium. Aw yeah! (It's feeble, I know.)

Not the ONLY game. Any MMORG, well any newer one, such as World of Warcraft, benefit a great detail as well. However with a 7800GT and 1 gb, on medium settings especially should be smooth as a babies butt. (BF2) may not be first person on map when loads, but Im so used to that already with 512mb in just CS hehe.

I said that.