A little confused

Mortah · 9 Jun 2006 at 09:39

I've been reading about overclocking and dividers etc etc and am a little confused.

If you increase the speed of the FSP then it increases the CPU speed AND the DRAM speed. But then if you put a divider it slows the DRAM down again... so you end up with a faster CPU... why not just increase the CPU multiplier? :S

A.N.Other · 9 Jun 2006 at 10:12

As the CPU Multi on modern chips (A64s) is locked upwards (you can only reduce it - which won't help with an OC :rolleyes:

!). You have to buy an FX series processor to have the unlocked multi - which is why they are so expensive.

Joe42 · 9 Jun 2006 at 11:01

Remember the fsb also increases the HTT speed so you have to slow that down aswell by lowering its multi.

A.N.Other · 9 Jun 2006 at 11:34

Joe42 said:
Remember the fsb also increases the HTT speed so you have to slow that down aswell by lowering its multi.

Yes, don't forget this! There is an HT or LDT Multi somewhere in your bios. It will default to 5x (sometimes displayed as 1000) and needs to be dropped to 4x (800). If you get your FSB speed greater than 250, it need to be dropped to 3x (600).

Sparky · 9 Jun 2006 at 11:46

Run mine at 3 as RAM is running 280.Just try to keep it below 1000 basically.

Mortah · 9 Jun 2006 at 13:30

Ahhh... so the moral of the story is to increase FSB and so increase speed of CPU... then decrease speed of the RAM & HTT using dividers... have I got this right?

Does anyone have any links to decent overclocking guides for modern CPUs as I can only find ones for the older CPUs which involve FSB / multi fiddling

A.N.Other · 9 Jun 2006 at 14:12

That is correct.

Being an amazingly nice guy - and rather bored - if you give me your spec, I'll do you a walkthrough. Well, actually, I only need the mobo name and CPU.

Joe42 · 9 Jun 2006 at 14:45

Best if you tell us what you've got and we can guide you though step by step.

A.N.Other said:
and rather bored

I'm supposed to be revising... which amounts to the same thing

A.N.Other · 9 Jun 2006 at 14:56

Joe42 said:
I'm supposed to be revising... which amounts to the same thing

Ditto. Got my first A2 exam on the 19th

. But in the mean time, Biology revision is boring!

// EDIT // You're my age, so I take it you're doing the same thing. Good luck n'all

Joe42 · 9 Jun 2006 at 15:04

Supposed to be doing A2 electronics revision, which may sound more interesting but i can assure you its not.

Then i have the computing exam to look forward to, where i have to answer a number of questions with technically incorrect answers to gain marks.

For example, the question 'what is pagefile' would be marked correct if i said 'an extension of main memory' even though that is not actually the case and a system with gigabytes of memory will still make use of a pagefile.

If i said 'pagefile is used to store low priority data' it would get marked wrong. :mad:

I've seen this asked on this forum and a number of people confirmed that pagefile is not an extension to memory.

And then there are a few really stupid ones such as getting no marks for 'hard disk' but full marks for 'hard drive'... I've got a whole list of these stupidities somewhere.

A.N.Other · 9 Jun 2006 at 15:25

Joe42 said:
Then i have the computing exam to look forward to, where i have to answer a number of questions with technically incorrect answers to gain marks.

Quoted for amazing truth.

I do computing too. They give you enough time in the exam to train a chimp AND get the chimp to answer all of the questions correctly, before the time is up - possibly even with time to spare. One guy in my set finished one of last year's exams in half an hour and only dropped 3 marks!

Anyway, Mortah, stop slacking and give us some info. We're going out of our minds here

Joe42 · 9 Jun 2006 at 15:39

You find it easy?
I find it quite hard mainly because i'm forced to give 'incorrect' answers to gain marks.
Some of the Hex and 2s compliment stuff etc is frankly mindboggling...

I also noticed that the official textbook states that clockspeed is the factor that determines performance.
I could spend hours picking incorrect statements out of that book and it drives me mad.

The other thing that drives me mad is both my teachers are technically incompetant. They both struggle to turn on the projector and have to ask the technition and one doesn't know what a heatsink is as the last pc she saw didn't have one.
It annoys me that the technical knowledge i have that allows me to help people on here and fix all sorts of wierd and wonderfull pc problems isn't examined at all.

A.N.Other · 9 Jun 2006 at 15:45

My teacher is ace - he wrote the program that we learnt to program in, along with a lot of other stuff! He's given us a 70 side revision booklet with everything you need to know. The thing with computing is that you have to disregard what you know and just learn it parrot fashion. I did CPT4 in Jan, so with my project, I need about 20 marks in CPT5 to get an A

.

Joe42 · 9 Jun 2006 at 15:48

A.N.Other said:
The thing with computing is that you have to disregard what you know and just learn it parrot fashion.

Your absolutely right and thats what i hate about it.

Mortah · 10 Jun 2006 at 00:54

Heh... X2 3800+. Asus A8R-MVP.

I think my age must be wrong... I've _just_ finished my degree at cambridge. Did two years of maths then a year of computer science.... In some sense a page file _is_ an extension of main memory... but thats such a slack understatement that it's not really worth saying... so yeah, you are right in what you say but they want you to be less precise... just learn to please the examiners

A.N.Other · 10 Jun 2006 at 10:34

OK! Good choice on the processor ... you can look here for overclocks with it. That table will help you see what settings you need to get a decent clock - there's probably even somebody with you board (cba to look

, even though I did it)

Download Prime95 and SuperPi for stress testing. Get CPUZ for info on your OC.

Here ... 2nd pic ... set the memclock value to 166MHz.

I can't find a pic, but somewhere in BIOS is a HT (maybe called LDT) multiplier. This will default to 5x (maybe displayed as 1000) and you need to change it to 4x (800) - see the table at the top.

... 1st pic ... raise the CPU Frequency. Using the table as a guide, you can jump up to say 240, probably without having to ramp up the volts. Put that in and see if it boots (it should do). Raise the CPU Fre. from here in 5MHz intervals until you get instability during testing. Bump up the volts a bit (using the table as a guide) and test again - and raise the frequency again. Continue, until your loaded temps hit 50Cish, or until you don't want to go any further.

Basically, stress test it at every raise in the FSB and watch your temps. If you go about CPU Fre. 250, the HT Multi will need to be dropped to 3x (600). If, in CPUZ, the RAM frequency goes above about 215-220, drop the memclock value.

That should be it. Ask if you want any more infomation.

Joe42 · 10 Jun 2006 at 10:59

A couple of things to add to that.

When or if you raise the fsb over 250 make sure to lower the htt multi to 3.

Overclocking is limited by the temperature of the chip and the volts your willing to put through it. Keep temps less than 55 and volts less than 1.55 to be safe and see how high you can get it within those constraints.
When your done, run prime95 for several hours to make sure its stable.

A.N.Other · 10 Jun 2006 at 12:11

Joe42 said:
Overclocking is limited by the temperature of the chip and the volts your willing to put through it. Keep temps less than 55 and volts less than 1.55 to be safe and see how high you can get it within those constraints.
When your done, run prime95 for several hours to make sure its stable.

That's good stuff. Make sure when you're testing that you run two instances of either Prime95 or SuperPi, as it's a dual core CPU.

I put the bit about HT in though

daveydave · 10 Jun 2006 at 16:50

Mortah said:
Ahhh... so the moral of the story is to increase FSB and so increase speed of CPU... then decrease speed of the RAM & HTT using dividers... have I got this right?

Does anyone have any links to decent overclocking guides for modern CPUs as I can only find ones for the older CPUs which involve FSB / multi fiddling

this whole divider thing....its an AMD thing right...cos check my sig...to overclock all i did was punch the fsb up in 10's then when it started failing stress tests lower the increments i was working with and increase the voltages?? havent touched mem timings or freqs...left it on auto