DDR vs. DDR2

This has probably been discussed before, but...

I'm a little at a loss to figure out how DDR2800 CAS 5 is going to
perform better than DDR400 CAS 2.5.

Any explanations would be appreciated.

TIA

Cessna 310 wrote:
>
> This has probably been discussed before, but...
>
> I'm a little at a loss to figure out how DDR2800 CAS 5 is going to
> perform better than DDR400 CAS 2.5.
>
> Any explanations would be appreciated.
>
> TIA
>
>

Higher bandwidth.

Latency is the same, sort of (as the protocol is not exactly the same
for the two technologies).

http://www.xbitlabs.com/articles/mem...dr2-ddr_3.html

According to an update blurb in this article, "posted CAS and
additive latency" are not being used by desktop chipset makers.
So I guess for the motherboards we use, the Xbitlabs comparison
numbers should be a good fit.

http://www.lostcircuits.com/memory/ddrii/

Your DDR2-800 stick bursts at 6400MB/sec and the DDR400 stick
bursts at 3200MB/sec. Both DIMMs are 8 bytes wide, thus the
multiply by 8 thing.

Paul