Beginners Guide to Overclocking

I have always worked out dividers this way

In this case 3:4 so the fsb is 375mhz

Divide 375 by 3 (first number in divider) gives you 125

Multiply that by 4 (second number in divider) gives you 500

Hence 500mhz and as the ram is DDR (double data rate) brings it to 1000mhz, the specified rating for that ram!

If it was set to 1:1 the ram would be running at a reduced total rate of 750mhz

Hope that's explained it ok?

Lee
 
Hmm that's confusing hehe :)

Simple maths way:

RAM is DDR, meaning it doubles it's speed.

1:1 ratio = FSB x 2
(e.g. 266 FSB = 533 RAM)

3:4 Ratio = [(FSB/3)x4]x2
(e.g. 266 FSB = 709 RAM)

Ratio is a fraction, above jsut means the RAM is 4/3 (four thirds) of the FSB. You then multiply by 2 (BIOS already does this for you) to get the DDR speed.
 
Oh, i've flicked through previous posts briefly, noticed the stress test mention plus other good advice, but i'd like to comment on Prime95.

Although i may sound hypocritical as i myself test with Prime95, i do not at all think it's a good stability test for 90% of users to use:

Small FFT's being the worst. For example, i can run programs like OCCT that will run my CPU at 100%. It will create about 10C less heat than Small FFT's test. Basically, like it says, it's a torture test designed to try and break the CPU (not literally). It has no relevance to real-life use, except someone who likes encoding 4 video's at once. You'd be going some to use a modern CPU to 100%, i know it would be impossible with mine.

It's like asking someone to kick me in the nuts to see how tough i am; "is he dead yet?" "No!" "kick him again, but harder!" "i don't think he can take anymore, he's proven he's tough", "rubbish!, get my high heels!".

Blend however tests the machine as a whole (actually like you'd use it), and seems a bit more forgiving.My temps with Small FFT's peak at 71C at 3.4ghz, but i can safely say i'll never, ever hit anywhere near that no matter what game/program/CIA spy satellite i run
 
But the point is, by thoroughly testing now, reduces the changes that in 6months time, or on a hot day you find your PC starts falling over leaving you thinking that your PC is dieing.

6months of accumulated dust or the 30C days of summer can be unforgiving on cooling systems and there's always threads in summer where people are having stability problems because they pushed their CPU just a fraction too far earlier on.

Blend (or more specifically the Large FFT) test has it's place as an overall CPU/NB/RAM tester, but it's always best to test individual components first so you don't end up in a situation where something fails but you're not sure which component it is.
 
Thank you both for that:)

One other dumb question I'm not getting an answer for, If Vcore is to low after tweaking down what will happen? Restart?

Oh, and should I disable smartstep or whatever the damn thing is called?
 
It's very much a personal thing, Intel Speedstep is a lot more stable than Cool and Quiet when overclocking, so you won't have any problems if you're overclocking.

If your CPU isn't getting enough volts, it'll either just fail in the stress test, lock up, blue screen, reboot itself, or crash loading windows/lock up at POST. If you make a big jump in clock speed without increasing voltage to match it is possible to corrupt your Windows install on booting.
 
The most popular reason (for me at least) for an stress test failing is not having enough vcore to match the FSB. I need 1.475 to be totally stable at 3.42Ghz (380 FSB). At 3.46Ghz (385 FSB), it fails within seconds.

However, it'll start windows on as little as 1.37, so shows you how different apps react.

However, if you find you can't post, it boots wierd or says overclock failed!,then it's usually your RAM, which for me is rubbish. Last time i buy corsair. Sure i can overlock it to 19378476472884374mhz at a high ratio, but the point is a need it at 1:1, and the max it'll give me regardless is 832mhz, which is pathetic for performance RAM tbfh.
 
Thanks for that again guys.:)

Oh, and 380 FSB is still ok to go with the 2x RAM divider right? since this would be lower than the 800Mhz

Find myself looking at 3.4Ghz now ;)
 
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Would give you same result as me yes. I assume you mean 1:1 ratio, yeh it'll give you my settings:

FSB: 380
RAM Frequency: 760
Multiplier: 9/Auto

Though i changed my Ratio to 5:6 (my motherboard has a drop down list, can just pick the RAM frequencies off), so Ram is 913mhz i think.
Add's about 90 marks to 3d mark 2006 heh.
 
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