My Acer 8943G supports DDR3 1333MHz but comes installed with 4GB 1066MHz.
I want to add another 4GB (have Windows 7 so should support it) but am wondering about the performance difference between 1066Mhz DDR3 and 1333Mhz.
I niavely figured that the 1333 was 25% faster but a decent scout around google today has left me confused by latency and multipliers and whatnot.
Is 1333MHz much better, i.e. a noticable difference to 1066 when it comes to RAM?
I'm leaning towards just adding 4GB of 1066MHz but don't want to spend the money on that if I'd be better biting the bullet now and just replacing the 4GB 1066 with 8 GB 1333Mhz. (The 4GB 1066 wouldnt go to waste as my g/f also has an Acer Aspire that supports it so I could give her an upgrade from 4GB to 8GB).
Any advice on whether the 1333 is worth the extra outlay?
Also, I beleive that I'm best adding matching memory, so adding 4GB 1333Mhz to the current 4GB 1066 is not advisable. Is this correct or have I misinterpretted that?
"Is 1333MHz much better, i.e. a noticable difference to 1066 when it comes to RAM?"
Very slight.. That 25% speed increase would feel more like 5% or 10% (If it's even noticable at all) On the other hand a low Latency can also increase the speed of the memory and if your current memory has a higher latency and you buy all new memory running at 1333 with low latency it would likely feel more noticable.
"Any advice on whether the 1333 is worth the extra outlay?"
I really don't think the 1333MHz speed will seem fast enough to justify the extra cost. I would just stick with 1066 and upgrade the AMOUNT of memory to 8GB. Your are almost ALWAYS better off going with MORE memory over faster memory.
"...adding 4GB 1333Mhz to the current 4GB 1066 is not advisable."
That is correct, DO NOT BUY MEMORY THAT IS NOT THE EXACT SAME.