question about OCing with DDR..

I know SDRAM.. I know RDRAM.. but I am building my first OC'd DDR system..

I am still kinda shaky on how DDR overclocks..


I am going to be running Samsung PC2700 in an Abit BD7-II RAID board.


I am PLANNING (keyword: planning) on running a 2.0a @ 2.66 using 133FSB.

I have 3:4, 4:3 and 1:1 ratio settings..

So am I right when I say the following:

3:4 would put the DDR at a measly 100/DDR200..?

1:1 would put it at 133/DDR266?

4:3 would put it at.......177/DDR354Mhz? (overclocked DDR 333 basically??)

I want to make sure I got the ratio thing down..

To figure it out, you take your FSB, say 133Mhz.. then if have a 3:4 setting, you take 133 / 4 * 3 = DDR speed? Is that correct?

If you had 133FSB and did a 4:3 setting:

133/3 * 4 = DDR speed??

Im not sure exactly what you are asking as DDR is not measured in terms of speed it is measured in terms of theoretical bandwidth.

PC2700 = (166 MHz Operating Speed) x (2x Rising & Falling) x (64-bit Bus) / (8 bits per byte) = 2656 MB/s available bandwidth.

DDR is also more indentified by the bus speed that the memory is being run on ie 266 DDR runs on a double date rate 133 mhz bus.

Yes, I understand all that.. I guess my post looks like a cluster-F.. heh

Basically, I want to understand the Ratio settings in the BIOS.. like 1:1, 4:3, 5:6, etc..

Some boards express the ratios different.
My board uses 4:3 1:1 4:5 2:3 for 133mhz and over.
It's easy with my board because it also shows you the result for your memory speed.

Some boards reverse the cpu expression and the memory.

What you posted is right or close enough.

On my board at a 133fsb 4:3=200ddr 1:1=266ddr 4:5=333ddr 2:3=399ddr

here's a link for you... I posted it in the intel cpu forum... it should help you...

http://wallacebw.homelinux.com/oc/

Brian

Oh.. my.. god..

WALLACE, you are the *MAN*

Thanks!

no prob...

I like it

Brian