No not exactly 2 times faster. Just 2 times the theoretical bandwidth or something. You will see a 10% gain at best in bench marks, but you cant tell the difference in real life. And thats odd that 1 module costs a lot less. Usually they cost the same here on the US
-And yes you can just add another 8 gb in to make it two channels. Although they dont have to be the same brand and model, make sure they run the same frequency and timings or else your mobo will throttle the faster one until they both match.
Dual Channel provides a 10-15% performance boost, not near twice as much, what happens is a stick of DRAM is treated as a 64bit device, when dual channel is enabled the 2 or 4 sticks in dual channel are seen as a single 128bit device, so it runs faster........And yes you can try adding another stick, they may or may not work together, even if the same exact model...also if 1600 or better XMP won't work, XMP is programmed into the sticks by the packaged set, which is why DRAM is available in so many different configs of sticks
Well, what is the motherboard and the CPU you have or you are looking at? If your system supports single 8GB module then you should be fine else there is no option you will you have to go with two 4GB modules.
yo man this thread is so old why is it still being discussed lol.
I'm not agree. This thread is old but the question and the answers still valuable for everyone looking for it, Google and other search engines still link to the old threads. It's a wast of time by reading through threads without finding a clear answer of your question. Thanks to all taking your time sharing your knowledge, posting your answers (even the old threads). Hundreds, thousands newbies will read and appreciate your contribution. Keep doing it everyone!!
Also . .if you are in the market for second hand ram, you can often pick up dual channel kits of what where originally more expensive branded lower latency (gaming) ram cheaper than single sticks of the equivalent overall size in proably a less prestigious brand. ie .. cheaper dual channel kits, faster CL .