Intel Core i5 Bus Speed/RAM Speed Confusion

[frozeninferno]

I'm about to build a computer for the first time, and I decided to go with the i5. On this website, it says I should get memory at around 3/4 of my bus speed. Is this referring to real speed or effective speed?

Also, this is kind of confusing since RAM speed is measured in MHz while the bus speed for the i5 is measured in GT/s, but I read on Wikipedia that 1 GT/s is basically equal to 1 GHz (is this true?).

And lastly, when you see something like "4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10600) Dual Channel Kit Desktop Memory", what does 1333 represent?

I am so lost, please help.

EDIT: How would these rank in terms of performance:
1066 MHz with 7 cas latency
1333 MHz with 9 cas latency
1600 MHz with 8 cas latency

 

[photonboy]

To be more clear:
Your RAM communicates with your CPU through the Memory Controller. The memory controller was always on the motherboard but has started to migrate into the CPU.

You are limited by the slowest component of either the Memory Controller or the System RAM. In many cases, however the Memory Controller is overclockable (especially in a CPU with a good quality after-market heatsink).

Basically ignore all the information and get either 4GB or 8GB (8GB rarely makes much difference especially if you have an SSD as your main drive) of:

DDR3 1600MHz @7-7-7-24 (or 9-...)

*No single-GPU graphics card can come close to bottlenecking a $200+ CPU. All overclocking does is add heat and fan noise.

I overclock my CPU (through my Gigabyte software) only when transcoding videos. I then set it back to its default settings when I'm finished.

 

[camprocps]

Thanks photonboy for your inputs!

I'm having a sony vaio cw with core i5 (PM55/Bus speed 2.0g). The laptop default RAM is a 1066Mhz 2G+2G.

I'm having a tough time playing starcraft 2. So i'm trying to get a fastest RAM out there into my laptop. possibly 4G+4G.

So i'm wondering whether i should get a 1600Mhz LC7 or a 1333 LC9 will be sufficient? ( i can't find a 4G 1333Mhz LC7 on newegg)

by the way, i won't overclocking my laptop.

 

[photonboy]

I thought you were building a desktop.

There is no reason for you to get more or faster RAM for your laptop. It won't make the slightest bit of difference for any video game.

You are being limited by your graphics chip, which unfortunately is not upgradeable in a laptop.

There's absolutely nothing you can do to make your laptop run video games better.

 

[photonboy]

Let's consider this thread CLOSED.