I'm trying to understand the overclocking process

nickv360

Member
Nov 23, 2004
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Okay, I've decided that I want to build my new rig, and overclock it to maximum potential(while maintaning stablity). For these purposes, I've come up with this rig:


https://secure.newegg.com/NewV...&WishListTitle=My+List

Now, what I don't get is the FSB part. The processor (e6320) has an FSB of 1066. So(now this is what I understand but could be wrong.), since it is dual core, it's actual fsb is half of that? So this is 533? But then for some reason, you have to divide that number by two agani. Not really sure why, but this gives you a real time clock speed of 266.

So that number is what is going to appear in the BIOS as your real FSB. And then, to over-clock the chip, we increase this number by small increments to see if it works. The multiplier for this chip(i think) is 7, so multiply this number 266, by 7 to get the initial speed of the processor, and as we increase the FSB, we multiply the higher values by 7 to get the overclocked speed.


Now this is all just my understanding of things, and there's a good chance I'm way off base here. But if I am right, then that leads me to my next question: ram.

As we increase the fsb values, we will eventually be limited by the ram right. So if the FSB is going at 266mhz, I need ram running at that speed in order to not be bottlenecked. And as I increase the cpu FSB, I need to keep the RAM speed greater than or equal to it.

If I want to get the CPU to 2.8GHz, I need an FSB of 400Mhz, so I need RAM running at 400Mhz right? Does the increased FSB speeds mean I need to change speeds in which the PCI-E ports and SATA ports communicate with the CPU?

I know I am new to this, so I would appreciate any input/help about this.
 

MustISO

Lifer
Oct 9, 1999
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If the processor runs on a 1066 FSB the processor speed is 266Mhz. You multiply 266x4 to get 1066Mhz.
 

nickv360

Member
Nov 23, 2004
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I was more confused about how the ram and other parts factor into the OC process. Things like the PCI-E ports and PCI ports going to need to be adjusted? And how exactly does the RAM OC process work? Does the speed of the RAM need to correlate to the speed of the FSB, and how do I know what speed needs to correspond to what?
 

Shimmishim

Elite Member
Feb 19, 2001
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PCI-E and PCI frequencies do not need to be adjusted. just be sure to set them at 100 / 33 respectively.

Older boards did not have pci-e/agp/pci lock and would increase as you increased your fsb and would cause hard drive corruptions and other problems.

as for ram... you just need to learn how FSB is related to mem frequency.

if the system is setup for 266 mhz fsb and your memory is running 1:1 then your memory frequency is 533 mhz (double that of your set fsb).

so...
266 fsb = 533 mem = ddr2-4200
333 fsb = 667 mem = ddr2-5300
400 fsb = 800 mem = ddr2-6400
500 fsb = 1000 mem = ddr2-1000

then you have dividers which make your mem frequency run higher than your set fsb

so for 4:5
you set fsb at 400 and your mem runs at 500.

there is 2:3
you set fsb at 400 and your mem runs at 600.

the 680/650 nvidia boards has the ability to unlinked fsb/mem so you could set your fsb at 400 and your mem at 410.

 

Hauk

Platinum Member
Nov 22, 2001
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You'll have to really read the guides, no one's likely to explain it all in a post.

A quick answer... dividers. You'll be doing 1400 divided by 4 times 8 to arrive at 2.8GHz.

The memory uses a divider and does not have to run at the fsb speed. You'll probably be between 700 & 900 on mem speed...
 

GuitarDaddy

Lifer
Nov 9, 2004
11,465
1
0
The easiest I can explain it it

Stock CPU core clock is 266mhz

Memory speed is mem ratio x core clock (stock is ddr2-533) 2.0 x 266

FSB is 4 x core clock, also refered to as quad pumped fsb (stock is 1066mhz)


Shimm explained the memory dividers/ratios pretty well

mem ratio 2.0 = 1:1 divider
mem ratio 2.5 = 4:5 divider
mem ratio 3.0 = 2:3 divider

couple of example of speeds I run in my rig

core clock 380mhz
8x cpu multi
4:5 divider

This gives me a CPU speed of 380x8=3040mhz, and mem speed of 380x2.5=ddr2-950

core clock 413mhz
8x cpu multi
1:1 divider

This gives me a CPU speed of 413x8=3304mhz, and mem speed of 413x2.0=dd2-826