What RAM to use

DDR3 is what you need for that mobo. Why do you need 32-bit Windows? Do you have exotic hardware or old programs?

4x1GB will run in dual channel mode, with 2 RAM modules per channel. 2x2GB will also run in dual-channel mode, with 1 RAM module per channel. 1 channel is one pair of same-colored RAM sockets. So if you have four RAM sockets labeled red, blue, red, blue, then putting two 2 GB modules in the red sockets will run them in dual channel mode. In my opinion, you should go for 2 GB modules instead of 1 GB ones. That way, you can have a larger RAM pool if you fill up all slots.

I suggest you get 2x2GB and get Windows 64-bit. If you already have a license key and the 32-bit installer, you can simply download a 64-bit original Windows 7 ISO and use your key. That should work fine.

Hi newcomer and welcome to the Tom's hardware forum.

1- What is your budget?
2- It's for game? video edition? surf the web?
3- Is better 2x2GB that 4x1GB.

$1500, gaming, and I was told that there is hardly anything compatible with 64-bit OS including new games but that must not be true, but no I don't have any old programs that I want to run I knew it was ddr3 memory so I might just go with 2x4GB, but who is the most reliable OCZ, PATRIOT, CORSAIR, my last computer used KINGSTON and it was pretty good, but the others I listed are better, yes? Thanks for the welcome.

Well, exist many good brands:

1- Corsair
2- Crucial
3- OZC
4- G.Skill
5- Mushkin (not all)
6- Kingston (not all)

DO you have the other components? With $1500 you can build a i7 rig.

I already have my Phenom II x4 925 because I figured paying $200 more for an i7 MoBo with crossfire support and the i7 processor itself, it wasn't worth a performance boost I would barley notice because I plan on OC my CPU to 3.4Ghz anyway so I'll still have a fast machine here was my first computer http://www.walmart.com/ip/eMachines-160-GB-W3650/972103....

My Components:
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

http://www.circuitcity.com/applications/SearchTools/ite...

http://www.circuitcity.com/applications/SearchTools/ite...

http://www.circuitcity.com/applications/SearchTools/ite...

http://www.circuitcity.com/applications/searchtools/ite... (already bought)

http://www.circuitcity.com/applications/SearchTools/ite... x3 (1 bought)

http://www.circuitcity.com/applications/SearchTools/ite...

Ok.

That's is a solid mobo. Good choise. But I can't see any GPU, What do you want use with that rig?

For now, I would change the PSU for this is a very good PSU an can support a X-Fire.

Also, change the HDD for the Spinpoint F3 1TB, is much better that the WD and more cheap too.

Lol I guess I did well this is my GPU http://www.newegg.com/Product/Product.aspx?Item=N82E168... and the PSU isn't fully modular, meh it's at the bottom of the case anyway so the cords I don't use will just sit there and there's less watts so I might need a 600 watts to power everything so perfect PSU when I xfire I'll get 1 GPU for now and the other later.

Well, you can see here the power requirements for your 5870.

"...500 Watt or greater power supply with two 75W 6-pin PCI Express® power connectors recommended (600 Watt and four 6-pin connectors for ATI CrossFireX™ technology in dual mode)..."

And you can see here all the X-Fire certified PSU.