PC2-6400 Laptop RAM tech details

I am thinking of changing the 1GB RAM in my new laptop. I searched in newegg and some of the tech specs that I don't understand. Appreciate your helps:

1) Just to confirm: 200-pin is for laptop, 240-pin for desktop, right?
2) Cas Latency: (5 or 6) what is this? which is better?
3) Voltage: (1.8V) all the same? do I need to care (or my laptop requires certain voltage that I need to check?)
4) ECC, Buffered/registered, heat-spreader: What is this? Is it important?
5) I saw that some have timings (something like 5-5-5-15) but most doesn't. Does my laptop only recognize RAM of certain timings?

I read that brand is not important for RAM. I found this from Transcend is the cheapest ($18):

http://www.newegg.com/Product/Product.aspx?Item=N82E16820208407

any catches? Or should I go for some better known brands like Kington ($21.5) or Crucial ($26)?

Thanks for your help.

 

1) Correct - it is usually 200-pin SODIMM
2) Lower is better, it represents a latency of the RAM - See Wikipedia on CAS latency
3) All the same
4) ECC is expensive and generally not worth it unless you're working on the highest sensitivity of calculations
5) Possibly the timings will matter, but generally most are standard numbers. For DDR2, 5-5-5-15 is certainly reasonable. Tighting those numbers down may depend on your motherboard, but I wouldn't worry about it. Stock numbers are fine.

Brand names don't really matter so much. I would say, get the best deal you can.

 

Thanks Evaders...

 

their is no such thing as ECC sodimm memory, so do not worry about it.
Other than that Evaders is spot on.

Just make sure that the memory you buy has a lifetime warranty

K-TRON

 

thanks again...

 

I've bought several Transcend modules and they have all worked OK for me.

At that price I wouldn't lose sleep over a lifetime warranty (whose life, the owner's or the equipment?).

John