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View Full Version : 5 mysterious cpu jumpers on mobo??


Matthius
09-07-03, 07:33 AM
ah, i just found five jumpers, all with 3 pins on em. all it says in my mobo's manual is cpu ratio selector?? what the hell are they for?

Pafet
09-07-03, 08:02 AM
isn't "cpu ratio" refers to manualy adjusting the multiplier when the CPU is moded or whatever, like in the old mobos?

what mobo you own?

B&R
09-07-03, 11:40 AM
Originally posted by Pafet
isn't "cpu ratio" refers to manualy adjusting the multiplier when the CPU is moded or whatever, like in the old mobos?

what mobo you own?

thats wat it most likely means. This was the way used to OC with old mobo's.

Do not change anytin until u read ur manual. Your manual should surely explain in detail wat they do.

Matthius
09-08-03, 12:36 AM
yeh, ur right with the multiplier thingies, (found out from other sources) but my mobo manual doesn't explain anything about it. it explains EVERYTHING on it, exept that...kinda stupid dont u think? well i'm pretty sure that my multiplier is on 15 atm. is it better to have a higher fsb or multiplier?

Dazz
09-08-03, 03:05 AM
It's probly on auto detect, which is 15x for and Athlon XP 2400+

EciDemon
09-08-03, 03:51 AM
Originally posted by Matthius
yeh, ur right with the multiplier thingies, (found out from other sources) but my mobo manual doesn't explain anything about it. it explains EVERYTHING on it, exept that...kinda stupid dont u think? well i'm pretty sure that my multiplier is on 15 atm. is it better to have a higher fsb or multiplier?

It depends on what your aims are, The multiplier only controlls the speed of your cpu. So at your default setting the bus speed and cpu speed is ... normal.

If you were to rise the multiplier a notch your cpu would be OCed. (System bus speed*Multiplier=Cpu speed) In my mobo manual it is refered to as Cpu clock speed (100,133 or 166mhz where default for my cpu is 133*15=~2ghz) By rising the multiplier in this case would result in a cpu OC by ~133 mhz. It might work but it might also be unstable so one would have to do some cpu stress testing and check temperatures and stability.
Lets say for the sake of argue that it didnt work, but you still wanted some more speed, then you could rise the System bus speed a bit and at the same time lower the multiplier so you endup with the same cpu speed as you had before. This is also an OC as you have a faster bus speed (affects memory, agp and fsb) Thus you get a bit more performance out of your system. Best performance would ofcours then be a combination of both, a slightly higher bus speed and a bit faster cpu.

But you should take notice that there might be a risk in doing this so this is outside of your warrenties. Also if all the speeds are linked together (as I think they are in your case based on other posts by you) One of your pci cards might be the source of faliure. A chain is never stronger then its weakest link. It is a bit of gamble, Two exactly identical rigs might very well OC differently.

What you need to do is to dig out your calcylator and do the math before you change anything (again bus speed*multiplier), if you plan to oc do it in small steps at the time.

Also be sure to check out all the good OC guides around the WWW. There you get more detailed info on this, if you are lucky you will even find a guide suited to your mobo and close to your setup too.

EDIT: Oh yeah almost forgot, before you do anything like this, be sure to have good cooling and airflow in your case. Faster speed=more heat=more likely to be unstable

Matthius
09-08-03, 06:10 AM
ah, sorry to tell u, but everything u just wrote...i already new. but my question is still unanswered. would i be better of to have a faster system bus speed? or a faster multiplier speed? i'm a little confused by one thing. would i be better off having say, a multiplier of 12 and a bus speed of 166? or a multiplier of 15 and a bus speed of 133? thats my main concern. i've oc'd all the other factors exept for the multiplier. im trying to figure out which way would give better performance.

thanks.

Dazz
09-08-03, 07:57 AM
166x12 is faster than 133x15.

EciDemon
09-08-03, 08:03 AM
Dunno whats better ... I think its more like: What works for you.

Multiplier Sets your cpu speed based on bus speed times XX.
Bus speed is sort of the internal transfer rate.

Its important to know that the multiplier dosent alone give you speed or performance. It does not controll transferrates, it just sets your cpu speed.
With a higher bus speed you would have to have a lower Multiplier value so that the cpu speed would some what match (or be set a bit above) manufacturer speed.

Like if your bus speed is set to 133 mhz and your multiplier to 15 then you get ~2ghz, if you set the multiplier to 16 then that adds another 133mhz to your cpu and that might be too much. Then you could rise the bus speed, and compensate that with the multiplier by lowering it so the cpu speed gain is perhaps 100mhz, or some other odd number. To do that then you would have to set the bus speed to 150mhz and the multiplier to 14. that equals 2100, ... 2,1Ghz.

So best thing would be higher bus speed with a lower multiplier as when you calculate it (bus*multiplier) your aim is to have a value slightly higher than what you began with. To sum it up you would then have better internal transfer rates _and_ more cpu power.

A very good example of this is my old Amd k6-2 450mhz All I could oc it was another ~25mhz. not too good. But then I managed to get the same cpu speed gain but with a faster bus speed (Higher bus speed and lower multiplier value) thus i got alittle more performance yet with the same cpu speed of 475mhz and it still worked.

A good thing to know is that the multiplier affects your cpu, while the bus speed directly affects memory, pci, Agp and such things and Indirectly affects your cpu... as that is up to the multiplier.

If your pci cards or your memory for example can not handle higher transfer speeds then you would have to try and rise the multiplier only. You would then only get more cpu power. transfer speeds is still the same.

I am sorry if I was a bit unclear about this in my previous post and I hope I did better this time. Good luck

goofjb
09-08-03, 08:25 AM
Raising the FSB will always gain you more performace. However if you raise the FSB to high you will start to harm if not kill AGP, PCI cards. I killed a 440mx by rasing the FSB to high.

Edit: On nforce2 and up, kt400 and up, you can maunally pick the clock speeds for the AGP and PCI bus. On older mobo's like the one i was refering to above if you adjusted the FSB it would also change the clock speeds of the AGP and PCI buses. Hence why I burned up the card.

Matthius
09-09-03, 06:47 AM
well, i think that a creative 5.1 EAX, gf4ti4200 and pretty much nothing else SHOULD be able to handle 166mhz..

B&R
09-09-03, 04:01 PM
Originally posted by Matthius
ah, sorry to tell u, but everything u just wrote...i already new. but my question is still unanswered. would i be better of to have a faster system bus speed? or a faster multiplier speed? i'm a little confused by one thing. would i be better off having say, a multiplier of 12 and a bus speed of 166? or a multiplier of 15 and a bus speed of 133? thats my main concern. i've oc'd all the other factors exept for the multiplier. im trying to figure out which way would give better performance.

thanks.

The higher FSB the better but if ur ram cant handle those speeds then it is kinda pointless. The only way then u will get faster cpu speeds will be by increasing the multiplier.

If u have agp lock and faster ram then higher FSB is better since increasing multipliers will produce more heat.