Undervolting...

applebyk · Mar 24, 2004, 01:22 AM

I've undervolted by 2500+ (running stock speeds) to 1.25v. This, along with my vantec stealth fan, has resulted in 34degree load temps (running prime95 + sandra burn in). My questions are these:
1) Will undervolting things harm them as long as it doesn't cause instablilty?
2) Is it safe to undervolt the chipset?

Oh, also, I got my Kingston HyperX 3500 to run at 2-2-2-11, at default voltage!

**dj_stick** · Mar 24, 2004, 01:44 AM

it's safe to under or overvolt a component about +/- 10% of its nominal voltage

applebyk · Mar 24, 2004, 09:30 AM

This is 76% of its default voltage....so thats no good?

***Zardon*** · Mar 24, 2004, 11:00 AM

generally undervolting is for when you are underclocking to perhaps in some cases to run passively. I really wouldnt see the need to undervolt your CPU at stock speeds, I am fairly sure it wont cause harm but a cpu is designed to run at a certain speed/volts. Are you just concerned with temps?

applebyk · Mar 24, 2004, 12:03 PM

Well im wanting to have a very quiet computer, and at 1.25v it creates very little heat. And at 333mhz, i can run my ram at 2-2-2-11 (kingston hyperx 3500). It just seems to be nice...and this way, i dont have to worry about slowing it down when its 40 degrees in the summer!

Judas · Mar 24, 2004, 08:46 PM

ey.....true that is.... 40*C in the summer brings issues to our saskatchewan running machines..... one reason i TOTALLY didn't want to move upstairs...... cause this place starts to cook very quickly..... and seeing as i'm running stock cooling... i'm gonna be a tad bit on the screwed side...

**Roadee** · Mar 24, 2004, 10:15 PM

Quote:

Originally posted by applebyk
I've undervolted by 2500+ (running stock speeds) to 1.25v. This, along with my vantec stealth fan, has resulted in 34degree load temps (running prime95 + sandra burn in). My questions are these:
1) Will undervolting things harm them as long as it doesn't cause instablilty?
2) Is it safe to undervolt the chipset?

Oh, also, I got my Kingston HyperX 3500 to run at 2-2-2-11, at default voltage!

First things first, the voltage to your memory really isn't going to cause a heat issue inside your case. You are not going to harm your CPU by underclocking it, as long as it is running stable. But you really should consider building your case and your computer as a whole to be quiet and cool with the CPU you want to run, no matter what the speed. Changing out your case fans for 120mm fans and adding sound deadening material will help out alot, as will making sure to tie back you cables, as to not inhibit the airflow.

You never mentioned what heat sink you are using on that CPU. If you were to use the SLK 900 series with a big 92mm fan on a fan speed controller, it would allow you to run overclocked at a higher voltage and yet the same temps pretty much. Or even at stock voltage at stock speeds and lower temps than you have now. When the summer months heat up, the fan speed controller will allow you to turn up the speed if you need to, otherwise you can keep it low and almost completely silent.

If low noise and low temps is all you are really really your only concerns, then you need to build for them. And watercooling would answer all of you prayers when it comes to sound and temperatures!!

applebyk · Mar 25, 2004, 02:44 AM

Quote:

Originally posted by Roadee
First things first, the voltage to your memory really isn't going to cause a heat issue inside your case. You are not going to harm your CPU by underclocking it, as long as it is running stable. But you really should consider building your case and your computer as a whole to be quiet and cool with the CPU you want to run, no matter what the speed. Changing out your case fans for 120mm fans and adding sound deadening material will help out alot, as will making sure to tie back you cables, as to not inhibit the airflow.

You never mentioned what heat sink you are using on that CPU. If you were to use the SLK 900 series with a big 92mm fan on a fan speed controller, it would allow you to run overclocked at a higher voltage and yet the same temps pretty much. Or even at stock voltage at stock speeds and lower temps than you have now. When the summer months heat up, the fan speed controller will allow you to turn up the speed if you need to, otherwise you can keep it low and almost completely silent.

If low noise and low temps is all you are really really your only concerns, then you need to build for them. And watercooling would answer all of you prayers when it comes to sound and temperatures!!

I've got a Sonata case (modded), a fan controllers on the way....Volcano 12 hsf. I can overclock my 2500+ to 2.431ghz (221x11). Just...I'm wanting to try something different, ya know?

G@MeBoY · Mar 26, 2004, 07:14 AM

What ?! did anyone noticed that "1.25V" value that he mentioned ?! I havent heard of a mobo mobo that can set value lower thatn 1.4V yet. What mobo do you have dude ?! My xp2000+ (which is an excellent speciment) runs at 1.4V at 1400MHz. There is a theory saying that if CPU can run pretty much undervoltaged on default clock, it will also OC good.

so applebyk, please post your mobo model/manufacturer because I dont believe that there is a mobo that supports XP2500+ and can give only 1.25V on CPU.

as for your question on undervolting chipset, well, deffault is 1.6V and on all mobos I have seen it cant be set lower than that, but I am guessing that yours probably can, so there is no harm, just try to keep your imagination as far away from institutions where people in white work...

applebyk · Mar 26, 2004, 11:36 AM

Quote:

Originally posted by G@MeBoY
What ?! did anyone noticed that "1.25V" value that he mentioned ?! I havent heard of a mobo mobo that can set value lower thatn 1.4V yet. What mobo do you have dude ?! My xp2000+ (which is an excellent speciment) runs at 1.4V at 1400MHz. There is a theory saying that if CPU can run pretty much undervoltaged on default clock, it will also OC good.

so applebyk, please post your mobo model/manufacturer because I dont believe that there is a mobo that supports XP2500+ and can give only 1.25V on CPU.

as for your question on undervolting chipset, well, deffault is 1.6V and on all mobos I have seen it cant be set lower than that, but I am guessing that yours probably can, so there is no harm, just try to keep your imagination as far away from institutions where people in white work...

Specs are:
2500+ (AQZFA w.44, locked), at 1.25v stock speeds (does 221x11 at 1.775)
NF7-S rev 2
Volcano 12
Sonata + 380 Truepower
Iceberq on the northy
2 X 1200JB (sata)
liteon cdrw+dvd rom
9600XT @ 550/340 (will oc more when i get my 1U cooler)
and I just ordered a ton'o stuff from svc, so it gets better....

and yes, ive managed to undervolt the chipset by .1v and run prime95, haven't had a chance to try reducing it further.
Question: Should raising my AGP voltage increase my overclock? I know that the 9600's dont take much power because of thier smaller micron process....

Judas · Mar 26, 2004, 09:09 PM

actually.... some people say that a cpu that can be successfully underclocked to or even below the default of a model cpu... would tend to mean it's a mobile....

applebyk · Mar 26, 2004, 11:53 PM

Weird...I moved out to the farm, and I needed to clear the cmos. After it booted I set it back to the way I had it, and it ran fine. Very strange indeed...

Judas · Mar 27, 2004, 01:47 AM

i've encountered stuff like that.... move the computer.. (take it for a drive).... take it out.. hit the power button... nothin much happens.... reset the cmos.. set everything back up normal... and boots fine....

G@MeBoY · Mar 29, 2004, 06:58 AM

Are you saying that Abit NF7 boards can go under 1.4V for CPU ?!

applebyk · Mar 29, 2004, 08:30 AM

Ya, I think that it will go down to somewhere in the 1.1v range. Keep in mind that the cpu wont run at that voltage, it's just a value that is availible. I have rev.2, maybe thats why yours is different.