It's likely you will lose your DUAL CHANNEL RAM feature by sticking in a single stick of ram. I won't answer what DUAL CHANNEL is since you can google that but the speed loss may make your next question be "Why is my machine slower with more RAM?"
I'd look to getting a pair of memory sticks.
Since you only have 2 slots, I'd get such in pairs at the SAME time. Mixing sticks may not work for DUAL CHANNEL operation.
I have a Medion PC - mothorboard is MS-7042 - online checks say I have RAM slots but actually have 2. DDR dimm PC3200 256mb in there at the moment. Bought this...
1 x DIMM 1GB DDR 400MHz, PC3200, 2.5V, Non-Parity, Non-ECC, Unbuffered, 184-pin
DUAL IN-LINE MEMORY 128 X 64, 16 chips, HIGH DENSITY
Module no: NCPD7AUD0-50M8A NC 02061
Fits in the slot ok although it is shorter in height once installed that the existing 256mb RAM. I put this down to being newer technology hence they made it smaller.
When I run the PC with the new memory in it just goes to a error screen asking for safemode or windows normally amongst other things..whatever I click it just restarts the computer..cant get into Windows. Have tried the 1gb in both slots alone and with the 256mb...no joy. Any reasons why?
Surley if I have bought DDR DIMM pc3200 400mhz then it should be ok??
Appreciate any help, reagrds, Alix