This has always been a topic that confused me and I've read different opinions everywhere I look.
I currently have 2x2GB RAM in my Virtualization Server with 9-9-9-24 Timings and 1.8V.
I need significantly more RAM in it but I'm trying to stay on a budget. I can get either 2x4GB of RAM now (its a microATX with 2 slots) and have 8GB, or I can get 1x8GB (for about the same price) and have 8GB and eventually get another 8GB.
I know that if I only have 1 stick then I lose the whole Double Data Rate attribute of DDR RAM, but would that be a significant performance hit?
Also, would it be advisable to put one of the other 2GB in with the 8GB if they are completely different timings/voltages or would that just be too unstable?