grchris32 :
ron2456 :
Always get dual channel when using apu.
But then, wont I need to change sooner and it will also be more expensive?
Why would you need to change?
If you motherboard has 4 slots you won't need to change a thing.
Also, getting a kit is a much more reliable choice since they're tested to work together. Compared to getting a single stick now and later another one, you have much less change of compatibility problems if you already bought them together.
Also, there are a lot of mainstream 2xxx Mhz RAM that are actually more expensive than 3xxx Mhz RAM, therefore if you can, you should get the faster.
Well, either option you'll probably have to upgrade soon, since 8GB is slowly dying as the standard for gaming rigs.
IMHO if you can opt for 16GB right of the bat, get the 8GB stick alone and pray for the RNG whenever you wish to upgrade that. That worse that can happen is that they won't work @dual-channel, giving you a bit less of performance.