hi quick question .. thanks for the anticipated help..
New asus mother board dual ddr mother board 2 black slots 2 blue slots .. for memory.. it wont boot with one stick of 1g ddr.. do you have to install them in pairs to boot up?
thanks!

i've never heard of having to install ddr in pairs, thats for RD ram, as far as i know, which isn't very far. i mean if you are having problems try booting with a pair. also are you getting beeps when you turn it on? those indicate what problem you are having, ie: 3 short beeps could equal your video card, or 2 long beeps could equal your ram. try looking on the mobo manufacture's site for a list of what the beeps mean, or search for the type of BIOS you have, usually phoenix, on google.

its dual channel...so i think you need 2 x 512...i think...im not sure though

You don't have to have pairs. You have 2 memory controllers with 2 slots for each controller. Your manual should explain how to configure the memory. Of course to enable both controllers you need an exact match of memory installed in the proper slot on each controller. Itr isn't necessary to use both controllers. There are benefits under certain conditions. Again I refer to the manual.

If you don't get a single (POST) beep, the system is dead and you do not have a memory problem. Motherboard maybe!