Couple of questions on RAM...

I'm kinda a noob with laptops but I just want to know what are the advantages and disadvantages of having 2GB of RAM (2 DIMM) and having 2 GB of RAM (1 DIMM). Also what is the difference between Corsair and normal RAM?

 

Corsair is just a brand, like Kingston, OCZ, Muskin, etc.

As for differences, none but the price factor and upgrade factor. Notebooks have 2 slots usually, so one 2gb stick means one empty slot that can be upgraded in the future.

 

Having 2GB of RAM (2 X 1GB DIMM) will run in dual channel which will be faster than having 1 X 2GB RAM, but you lose the upgrade ability in the future.

 

the speed difference between single and dual channel is a highly debatable subject. in some cases it makes no difference at all but in others the difference is there but not so significant. synthetic benchmarks always have the dual channel setups as a lot faster but in real time usage, the difference is very little

 

The attached results from Sandra memory bandwidth benchmark tests may be of interest. The graphs include three scenarios all on the same computer (Samsung X60 plus with Intel 945 chipset):

(a) 2 x 512MB 667MHz (5-5-5-13-18). This was the memory supplied with the computer

(b) 2 x 1GB running at 533MHz (4-4-4-11-15) (I don't have 2 667MHz modules)

(c) 1 x 2GB 667MHz (5-5-5-15-20)

(d) 1 x 2GB + 1 x 1GB 667MHz (5-5-5-15-20)

The scenarios cover both 533 vs 667 MHz and one vs two modules. The results are remarkably close. That said, CPU-Z reports dual channel whenever it sees two modules, but they are not necessarily of the same speed or size.

I noticed with interest that the Memory bank cycle time (Trc) for the 2 x 512MB is only 5. Is this genuine dual channel at work? Normally the memory Trc is the module Trc + 1. However, even if it is real dual channel then the measured memory bandwidth is not boosted.

John