I currently only have 1G of RAM on my desktop, im looking for another stick to upgrade it to 2G. I dont know what i should get 
Motherboard: Acer E946GZ or 946GZT-AM V.1.0
My current RAM is DDR2 single channel PC2-5300 (333MHz) 240-Pin, unbuffered. but i went to a store giving this info, he told me that only DDR has 333MHz, and my computer isn't DDR2 compatible, and another guy said it might be clocked down to 333MHz to fit the system, i just wanan make sure i get the right one...
Motherboard: Acer E946GZ or 946GZT-AM V.1.0
My current RAM is DDR2 single channel PC2-5300 (333MHz) 240-Pin, unbuffered. but i went to a store giving this info, he told me that only DDR has 333MHz, and my computer isn't DDR2 compatible, and another guy said it might be clocked down to 333MHz to fit the system, i just wanan make sure i get the right one...