Ram Speeds

[tesco]

In lamseys ram guide is states that pc2100 is the ddr equivalent of pc133 sdram. Does this mean that it is the same speed as pc133 ram or will it be twice as fast (133mhz vs 266mhz)??? im confused about all this ram speed stuff.

Also my motherboard is limited to pc2100 ram only so if i was to buy pc3200 ram and put it in my computer will it dumb down to pc2100 speed like sdram does or will it just not get detected by my motherboard???

The reason why im asking this is because i might by another 512mb for my computer but it would be great if i could use the new stick of ram in my next computer.

[Smurfette]

It's always been the case that you can fit faster RAM and it'll work fine, just at a slower speed. Indeed, I have a stick of PC3200 (400MHz) in my system running at 333MHz.
Some motherboards nowadays can be finnicky about the RAM you use though... a few mobo manufacturers put a little list of tested and known good brands on the specs pages of their boards.

[tesco]

ok thats one thing clarified but is pc2100 faster thn pc133 or is it the same speed just ddr instead of sdram.?

[pc-gamer-dude]

pc2100 ram is twice the speed of pc133, it runs at 133mhz on double pumped, as in double date rate. giving you a bus speed of 266, as opposed to sdram giving you 133. so yes, it is double the speed.

[bigdawgfoxx]

No, its not the same speed.

Its DDR which is Double Data Rate. It runns at 133Mhz yes, but its DDR and not SD. So it actually runs at 266, or 133X2.

[Smurfette]

Originally posted by bigdawgfoxx@4 January 2004 - 23:34
No, its not the same speed.

Its DDR which is Double Data Rate. It runns at 133Mhz yes, but its DDR and not SD. So it actually runs at 266, or 133X2.

Hehe, don't confusethe lad!

You mean they both run at 133MHz, but the DDR RAM reads TWICE in each cycle, and so actually works twice as fast.

[tesco]

slightly confusing but i understand now thanks.