Memory compatibility - DDR

[ApoorvKhatreja]

I have a D101Ggc Intel Motherboard which supports only DDR RAM. I just wanted to know that if I wanted to add another stick of memory to the other slot that is currently empty, what are the conditions so that it is compatible with the previous stick of RAM?

[n2casey]

Clock speed/frequency must b same for both RAM sticks.

[ApoorvKhatreja]

So there isn't any issue with the size? I mean can I combine a 1 GB stick with 128 MB?

[n2casey]

Yes u can.

[codename_romeo]

u can definitely add.....but then it is not advisable as both the modules will take different voltages.....so if u can then add a 1 gb stick n remove the 128 mb stick

[ApoorvKhatreja]

How about a 512 + 256 ? And could you eloborate on the problems could arise with the different voltage intake?

[n2casey]

How about a 512 + 256 ? And could you eloborate on the problems could arise with the different voltage intake?

It will work fine if both sticks have same clock speed.
Regarding voltage, in a condition of different working voltage, ur system can hang, errors related to memory can occur or system will not boot.
I faced these errors when I was trying to upgrade my friend's PC.

[ApoorvKhatreja]

Thanks.