Question about ram slots

[sam432]

hey everyone i have a pc that im working on that has 2 1gb ddr2 800 sticks in it, taking up 2 dimms, with 2 more free. My question is if I buy an extra 4gb of ram, 2x2 gb, will i be able to put those in the extra two slots for a total of 6gbs, or does all of the memory have to be the same size?

 

[pat mcgroin]

I will depend on your MB.
Some MBs will want them in particular slots.

 

[sam432]

its a dell xps 630 with a NVIDIA® nForce 650i SLI chipset if that helps