Understanding OCing the 8800

[breathemetal]

Alright, Im a little lost here.

My card is pre oc'd @ 630/1000

but I see guys posting like....645/1350/2000

Whats that all about?

What do each of these numbers mean? And which one should I overclock for a "said" reason?

[mynakedrat]

not really,
core/shader/memory
the shader goes up with core increase.
and that last number 2000, its 1000x2. so yours is just right :)

[breathemetal]

Why is it multiplied by 2?

[mynakedrat]

eh, i dont know, someone else will i am sure.
but mine is 925 (1850mhz)

[breathemetal]

Alright, thanks

[Madpistol]

Why is it multiplied by 2?

Some people take the acronym "DDR" a little too seriously, so they double the given clock frequency of the memory. Some times, it's hard to tell which is right depending on the video card.

[breathemetal]

I used RivaTuner's hardware monitor to find mine.

I figured that was the best way.

[SlieTheSecond]

It is because it DDR. Double Data Rate.

One way to think of it is having a one lane highway (sdram) vs a two lane highway (ddr).

In the one lane highway you have 1 car going 100 mph carrying information a distance. But in the two lane high way, you have 2 cars going 100 mph each carrying information. They are still traveling the same speed, but the two lane highway will transfer twice the data than the single lane in the same amount of time. Effectively running twice the speed as the one lane highway.

An intel cpu is quad pumped meaning it has 4 lanes. The FSB for that is the fsb x 4. (ie 266fsb x 4 gives you an effective fsb of 1066mhz)

So 1000mhz x 2 gives you an effective speed of 2000mhz.

Thats not exactly how work it works, but a very simple way to think about it.

P.s. I think you can change the core and shader clocks individually by flashing the bios. Not sure though, haven't tried it.

[buffbiff21]

^ That highway analogy is not quite ideal.. Clocks operate based on frequency waves. DDR means data is transmitted on each peak and valley of the sine wave.

anyway, for some very informative stuff:

http://www.thetechrepository.com/showthread.php?t=133

[SlieTheSecond]

Hence why I said its a very simple way to think about it, and not how it works.

Maby I should have added "Do some google researching if you want to know exactly how DDR ram works"

[mynakedrat]

^l^o^l^