BleepingComputer.com: RAM: MHz vs GB

How important is the ram speed compared to the ram gb capacity? I guess the speed becomes more and more important the larger the gb (because of decreasing marginal utility of gb), but where is the threshold where one should start to really focus on the speed?

How well will ddr2 6gb 800 mhz perform compared to ddr3 4gb 1333mzh?

I guess the video card memory plays an important role as well? The more of this, the less gb ram I need?

I will use it for blu ray and some gaming, but Im not looking for an extreme gaming computer.

Will ddr3's lower power consumption make any difference when it comes to battery time and laptops?

A 32-bit Windows OS can only address 3.1-3.5GB, as some is reserved by the system. DDR3 can provide greater memory bandwidth, but the latency is higher.
DDR3 requires less voltage, so it will draw less power. BluRay playback is largely done in hardware on the video card. An inexpensive Radeon HD 4350 or the Nvidia counterpart will do fine, even for 1080p and 1080i VC-1 and H.264/AVC encoded content at 1920x1200 desktop resolution.

DDR3 will give you more "speed" for each individual task. If you need to run several memory-consuming processes at once, you'd need more memory - but 6GB? What are you running? It's a lot!

Thanks.

Nice to know bluray doesnt demand much, as long as the video card is ok.

Well, I dont need 6gb today. But who knows about tomorrow? (I see that Dell sells PCs with 12gb ram, what are those buyers running?) Anyway, I think it would have been interesting to know how to compare speed and gb in general, could have been other spesifications as well. And you, ErikJM, gives a clear answer, you dont need 6gb, which means that you probably think speed is all that matters when gb is at least 4?