Montevina RAM Question DDR3 or DDR2! (Timings)

Hey guys, I had a question one of the main things with montevina is the ram upgrade but Im looking into an ASUS and it has montevina but DDR2 ram at 800 mhz, which is what I wanted because Im assuming the timings on 800mhz is prob 4-4-4-12 or 4-4-4-15

But DDR3-1066 is prob at 7-7-7-21 which is a huge difference, Im assuming DDR3 is going to be slower than DDR2 performance for the first while...

Is this assumption correct?

 

Never heard of PC2-6400 CL=4....

Kingston HyperX is CL=5 (5-5-5-18), and the value-based models are CL=6 (and some good ones are CL=5)....

DDR3 latencies are numerically higher because the clock cycles by which they are measured are shorter; the actual time interval is generally equal to or shorter than DDR2 latencies. (Higher CAS latency but compensated by higher bandwidth, on the higher bandwidth modules)

 

This link has it as CL4.

Here is a speed chart as best as I can figure what you might expect from different Speed/CL configurations.

Time to first bit

Mhz	CL	ns/cycle	total time (ns)
533	4	7.5	30
667	4	6	24
667	5	6	30
800	4	5	20
800	5	5	25
1066	7	3.75	26.25

Time for 5 bits

Mhz	CL	ns/cycle	total time (ns)
533	4	7.5	60
667	4	6	48
667	5	6	54
800	4	5	40
800	5	5	45
1066	7	3.75	41.25

 

I guess laptop memory is different but desktop- DDR2-800 is always 4-4-4-12 and DDR2-1066 is 5-5-5-15

But because DDR2 has been out for a while now, I would assume they got DDR2-800 CL=4

 

OK fine if it is what you say here are the numbers.

Time to first bit

Mhz	CL	ns/cycle	total time (ns)
533	4	7.5	30
667	4	6	24
667	5	6	30
800	4	5	20
800	5	5	25
1066	5	3.75	18.75

Time for 5 bits

Mhz	CL	ns/cycle	total time (ns)
533	4	7.5	60
667	4	6	48
667	5	6	54
800	4	5	40
800	5	5	45
1066	5	3.75	33.75

But find SODIMM's that do this before you bet your money.

 

Desktop RAM usually has faster timings because it has higher voltages to make the electrons move more quickly.

We have past examples of erroneous advertising of RAM statistics. I will wait until someone tests a module and publishes the CPU-z report of the SPD table. At the moment I haven't seen such evidence to support CL of less than 5 at 800MHz.

John