Advice with Ram

[Jelvis]

I have 4 dimm slots on my motherboard. I currently have 1 256mb stick and a 512mb stick. I want to add more but Im not totally sure about dual channel.
To run dual channel do all ram sticks have to be the same size??
Im thinking about either getting a 1gb stick and leave it as single channel to upgrade even more in the future or getting 2x512mb sticks therefore i would have 1.76gb ram. Im guessing I need to buy 3x512mb sticks for dual channel to run, but then I'd have 3 ram sticks from 1 make and 1 ram stick from a different make. Anybody know what i should do?
Thanks

 

[Blakhart]

Hi
As to dual channel-ness, that depends. Matched sticks are always best.
If your system will even utilise dual channel mode with differing amounts of memory in each channel is a question too. Have to check your mobo maker to see what will happen when you mix ram up.