DDR-Ram - what's the difference

[RedCell]

I'm new to the DDR-business so I hope you can help me with this:
Some DDR-ram is being sold as being PC2100 C2,5 and some is being sold as being only PC2100. The former is approx. dobble the price of the latter. Why is this?

Regards
RedCell

 

[Guilty]

If CAS latency isnt specified, assume it's 3. 2.5 is faster than 3, hence the premium.

 

[RedCell]

That figures....
Do you guys think it's worth the extra money?

 

[njeske]

Guilty is wrong. There is no such thing as CAS3 in DDR memory. Only CAS2.5 and CAS2. CAS2 is the fastest and the most expensive. CAS2.5 is slightly slower, but can be a lot cheaper. If the memory is simply advertised as PC2100, it is very safe to assume that it is CAS2.5 which is the standard in DDR memory right now.

 

[pm]

njeske is right. There is only CAS2 and CAS2.5. FWIW, there is still free shipping at www.crucial.com - good prices and memory direct from Micron.

 

[Guilty]

Ah I forgot, thanks for correcting me. That aside, the modules you are looking at must differ somehow then? Do you see "registered", "ECC", "2400", heat spreaders? I assume the capacity is the same.