DDR Ram

[kré]

ok, so i'm kinda not up to speed on the intricaces of ddr ram.

situation:

i have a stick of 256Mb PC2700 DDR

a friend of mine wants to sell me a stick of 512Mb PC3200 DDR

now, what i believe from what i have read, if i stick these both in together, they will work, however the 512Mb will work as PC2700.

is this correct or am i completely off the track?

will they both work together? will putting in the 512Mb make the 256Mb completely useless?

enlighten me my geeky friends :cool:


edit: eep, i realise that i probably should have put this in hardware.

[sagit]

I believe the RAM will scale down to lowest rated speed. However, you need to remember:

1) The mobo needs to be able to handle the speeds

2) Chicks dig RAM

[BlueBoy]

The RAM speed will scale down to the slowest stick.

Make sure your board can handle that RAM.

[kré]

jawsome

and yes, my board can handle it -_-

[BlueBoy]

Originally posted by cray
jawsome

and yes, my board can handle it -_-

Then you won't be wanting the 256Mb stick. It's too slow.

*hint* *hint* :D

[kré]

Originally posted by BlueBoy
Then you won't be wanting the 256Mb stick. It's too slow.

*hint* *hint* :D

what for you wanting 256Mb stick.

[sagit]

Originally posted by cray
what for you wanting 256Mb stick.

blueboy is a chick. remember i said "chicks dig ram"?

:p

[kré]

Originally posted by sagit
blueboy is a chick. remember i said "chicks dig ram"?

:p

lol

[BlueBoy]

Originally posted by cray
what for you wanting 256Mb stick.

I have a spare slot. Although I should be filling it wih a 512Mb stick. :P

[Spingo]

I'm gonna throw a spanner into the works here. What was said above is NOT necessarily true.

It is true that both sticks will operate at the same speed. However, they will both run at the double the speed that your motherboard sets the memory bus to (hence the term double data rate).

Now, some defintions:
PC2700 = DDR333 = 167MHz memory bus speed.
PC3200 = DDR400 = 200MHz memory bus speed.

Now, for example, lets say that I have a P4 CPU that runs at a native quad-pumped FSB of 533MHz (my system bus is technically running at 133.33MHz). In order to make my RAM run at PC2700 spec, I use a 5/4 multiplier on the memory bus (133.33/4 = 33.33. 33.33*5 =166.66). Similarly, a 3/2 multiplyer should be used for PC3200.

So how fast will your RAM run? Well, it really depends on the multiplyer that you are using for your memory bus.

Just remember that both sticks will work at the same speed. You can easily overclock the PC2700 stick and underclock the PC3200. You might even be lucky to overclock both. Stability will be your only concern...

[kré]

okie dokie

i might get the 512 and sell the 256 to my father in law then

he has another 256 pc2700 stick :p