Ok, I checked out my motherboard, it's a
NextGen Electronics - GigaByte GA-7N400 Pro AMD nForce2 Chipset Motherboard Review which supports dual channel memory.
I bought 512 mb of the same memory I already had which cost 1500 baht.
I installed it with a little help from
http://www.kingston.com/literature/p...ualchannel.pdf - as Surasak said put the two in the same colour (in my case blue) which was as i guessed DDR1 and DDR3.
Great, all done.....now does this mean I can watch twice as much porn, or not????