Ram-Which slots

Motherboard Gigabyte GA-81PE1000 (-L) v2.0 (No manual)
Ram Slots x 4 DDR DIMM Bus Type DDR SDRAM
Memory Speed PC3200 (200mhz)
One stick of 512mb installed.

Ok I am technically retarded, so I need to check I,m buying 1gb DDR PC3200 • CL=3 • UNBUFFERED • NON-ECC • DDR400 • 2.6V • 128Meg x 64.

First question is it compatible with 512 stick? secondly, do I move 512 stick to slot 3, and put new stick in slot 1?

Thanks

Yes it should work.

theyre different capacities, so its not going to run dual-channel. i would reccommend just putting the 1 gig stick in slot 1 [or 0 depending on the numbering scheme of the mobo] and the 512 stick in slot 2 [or 1]

Someone should mention that there is a possibility the two sticks may not work together.

You're right, it is possible. I said 'should' assuming if they didn't we'd hear back.