OCing...

T

TrainTrackHack

VIP Member
Okay...as of yet, i'm not going to do any kind of overclocking. As a matter of fact, i don't even have a system to OC. But there are a few things i wana know bad...

Firstly, OCing multiplier-clocked CPUs. As far as i know, if the CPU is multiplier-locked, the only way to OC would be to increase bus speed. Also, if I'm right, this also affects memory speeds and possibly PCI-E...now this is the part where i'm getting confused. For example, you can get almost 100% overclock out of a Pentium dual-core, but you certainly couldn't get even close to OCing your memory that much...at least that's what i think. Explain, plz...how does this work out?

And for what i know, GFX cards and such will get sick of even a slight OCs of PCIE...this being another thing that i don't get.

Common sense tells me that things between AMD/Intel CPUs might work differently...info/help/advice from both POVs appreciated, thank you!
 
Almost all newer motherboards will have the PCI, PCI-E, and SATA busses locked, which means that they will not be raised when the FSB is raised. Now you are correct in saying that the memory speed will also rise with the FSB, however thats what memory dividers are for. If you set the memory in a 1:1 ratio, then at stock the memory will be running much slower the what it was at stock, however the point of that is to be able to overclock quite a bit before the RAM becomes a bottleneck.
 
I overclocked my q6600 from 2.4 to 3.1 by increasing the cpu fsb, but i unlocked the memory bus from the cpu bus. I guess not all mobos can do that, but as far as I'm aware, my memory speed has not changed.
I had the option in my bios to make the memory speed dependent on the cpu speed, or independent. Check out this link. It's a review of my mobo, showing the bios option to "unlink" the memory fsb speed from the cpu fsb speed.
http://www.overclockersclub.com/reviews/xfx_680_lt/5.htm
 
Nvidia4life said:
I overclocked my q6600 from 2.4 to 3.1 by increasing the cpu fsb, but i unlocked the memory bus from the cpu bus. I guess not all mobos can do that, but as far as I'm aware, my memory speed has not changed.
I had the option in my bios to make the memory speed dependent on the cpu speed, or independent. Check out this link. It's a review of my mobo, showing the bios option to "unlink" the memory fsb speed from the cpu fsb speed.
http://www.overclockersclub.com/reviews/xfx_680_lt/5.htm
Click to expand...
The nVidia 680i motherboards can have the memory unlinked from the FSB, while thats great for determining the maximum speed of the processor, you actually get much better memory performance running a lower divider, 1:1 being best.
 
ok, now, the next few questions may sound a bit stupid, but i just want to make sure that there's no slightest bit of confusion or whatever. So,

1)Core2 cpus run better if the memory speed is in sync with the FSB. So for example, if i OC my fsb from 800 to 1066, would I benefit from having DDR667/1066 instead of 400/800? Or how does this actually work...or am I getting something totally wrong and making a clown out of myself?

2)More detail about the mighty "divider". What's the number on the left-, and that on the right-hand side (like eg 2:1, what's "2" and what's "1")?

And finally...thx for everyone. Yea i'm being a bit noob, but you'll just have to get over it...

EDIT: I mean DDR533 instead of 667...
 
Last edited:
hackapelite said:
ok, now, the next few questions may sound a bit stupid, but i just want to make sure that there's no slightest bit of confusion or whatever. So,

1)Core2 cpus run better if the memory speed is in sync with the FSB. So for example, if i OC my fsb from 800 to 1066, would I benefit from having DDR667/1066 instead of 400/800? Or how does this actually work...or am I getting something totally wrong and making a clown out of myself?

2)More detail about the mighty "divider". What's the number on the left-, and that on the right-hand side (like eg 2:1, what's "2" and what's "1")?

And finally...thx for everyone. Yea i'm being a bit noob, but you'll just have to get over it...
Click to expand...
It's actually the FSB that determines the memory speed, not the bus speed (although they are related).

For instance, a stock Core 2 which has a bus speed of 800MHz would have an FSB of 200MHz (200x4 = 800). Now for best memory performance, the memory and FSB would be in a 1:1 ratio, however in this case the memory would only be running at 200MHz (400MHz DDR, so DDR-400). In order to get the memory to run at DDR2-800 speeds, the FSB would need to be at 400MHz.
 
So...if I got this right, DDR-### basically just tells the maximum speed the memory is supposed to be able to handle? It doesn't run at that or any other speed unless the FSB makes it so?

Did you mix up bus and FSB? I thought they'd have a 200Mhz bus, and since it's quad-pumped, that would make it FSB800?
 
hackapelite said:
So...if I got this right, DDR-### basically just tells the maximum speed the memory is supposed to be able to handle? It doesn't run at that or any other speed unless the FSB makes it so?

Did you mix up bus and FSB? I thought they'd have a 200Mhz bus, and since it's quad-pumped, that would make it FSB800?
Click to expand...
Thats what the memory is rated for from the manufacturer, it can run slower or you can overclock it and make it run faster.

If the memory is in a 1:1 ratio with the FSB, then you just double the FSB to determine the actual speed of the memory (DDR = double data rate).

If you leave the settings on Auto, then the motherboard will determine what memory ratio/divider to use to get the memory at the rated speed, such as DDR2 800.
 
You must log in or register to reply here.
Back
Top