Page 1 of 1

Undervolt mod Athlon XP 2000+

Posted: Tue May 31, 2005 5:15 am
by kristofer
Hello!

Long time reader fisrt time poster!

I have an Asus A7V-266C motherboard and a Ahlon XP 2000+ (TB core).
Since the Asus board is unvilling to undervolt my CPU, I was thinking about moddig the CPU.

I read topics such as
http://forums.silentpcreview.com/viewto ... olt+athlon
and
http://forums.silentpcreview.com/viewto ... highlight=
but I'm still a bit confused...

What kind of voltage do you guys recommend for a XP 2000 TB?
My motherboard currently allows 1.6 ~ 2.10 for my CPU...

And if I lower the voltage too much (by modding) I fear that my computer won't start up anymore. :?

Any thoughts?

Best Regards
Kristofer

Posted: Tue May 31, 2005 8:04 am
by sonuvbob
I'm actually thinking about doing the same thing with my Palomino XP 2000+ and ASUS A7V333. I think if you mod the L11 bridges to lower the voltage, the boards will treat that as the lowest voltage possible, and let you "overvolt" it from there. I was planning to set mine to 1.1v by cutting 3 bridges, figuring I could set the voltage between 1.1v and around 1.5v. However, I don't know the min voltage the board will allow- I think it's 1.1v.

I'll also have to open the L1 bridges, which I don't have the means to do right now; otherwise I'd do it today and let you know how it went (I don't think I'll be able to get it to boot at low voltage with the 12.5 multiplier- FSB only goes so low)

Posted: Tue May 31, 2005 11:14 pm
by VERiON
kristofer - welcome to SPCR !

> What kind of voltage do you guys recommend for a XP 2000 TB?

rule of thumb - you can easily lower voltage by 0,5V (stock settings), if you underclock (say 1600+) you can lower voltage to 1,475V

> And if I lower the voltage too much (by modding) I fear that
> my computer won't start up anymore.

make sure that your mobo bios allows OVERVOLTING, because if you permanently mod your cpu (1,475V) you can always OVERVOLT in bios to have 1,6V or 1,5 if your computer hangs at low Vcore voltage. It's good to have backup CPU (anything that fit into mobo) in case your computer won't even boot to bios - in that case you can put backup cpu (it can be your friend's cpu :D - it is 100% safe operation), enter bios and make some changes (lower FSB, rise Vcore) and than insert your cpu again.

If you don't have spare CPU, try to set max OVERVOLT and lowest FSB (ie 66Mhz) as bios defaults - some bioses have option to save current settings as bios defaults (or you can mod your bios BIN file and flash it). In that case - when you reset your bios settings (via mobo jumper) you can likely boot with your 1,475V moded cpu, because it will be running on max OVERVOLT (close to its standard voltage) and with lowest FSB.