did the voltage mod (KT7A), how far can I go?

[Lasse S.]

My 1GHz AVIA chip wouldn't go higher than 1.4Ghz at 1.85V Vcore (look at my sig for spec)...since I'm water-cooling, I though I might try even higher voltages...I did the mod described here:

http://www.extremeoverclocking.com/articles/howto/Extreme_Voltage_Mod_1.html

well, it worked fine and at 2.14V I was able to run the chip at 1.53GHz....but this seems very high....I'm getting 46C at full load....should I throttle back a bit?

BTW! I installed a big passive heatsink on the 6 MOSFET's

[Colin]

I have found that after running at about 2.16 volts for a few weeks, backing off to about 2.06 will allow a little more speed. Burn in?

[Lasse S.]

Yeah =)

Well, I played some with it yesterday...I closed in on 1.6GHz with a Vcore around 2.20V....it was stable enough to do a couple of rounds of Prime95 Torture tests, but suddenly the thing rebooted....I have mounted a big heatsink on the 6 power regulators (MOSFET's) Even got a temp probe temporarly installed there....and during this test it passed 40 deg C....I think the main problem when going beyond 100Watts (according to radiate) is the mainboard cpu pwersupply incapable of delivering smooth power to the CPU....so this seems to limit itself....

But I noticed I could lower the Vcore some to get stable 1.53GHz operation afterwards.....this is a fresh setup, so some time might allow it to run more efficiently (Voltage wise)

Also using the ACPI (HLT on idle) is a no go with such a powerhungry CPU, as the instant on/off throtteling probably creates spikes in the CPU power regulators...the setup was A LOT stabler after disabeling ACPI....also an indication of a weak supply...

PS! I'm using a 550W Enermax (650W peak)

[Lasse S.]

A couple of pics, this was a easy mod...incase someone wants to try it themselves....

[Lasse S.]

one more....

[TT120]

So each of those connections goes to ground through a resistor? That seems pretty easy.

[Lasse S.]

TT120 (May 12, 2001 09:06 a.m.):
So each of those connections goes to ground through a resistor? That seems pretty easy.

Yeah, please take a look at the link in my first post in this thread...

[Lasse S.]

Maestro (May 12, 2001 10:10 a.m.):
What is the max that mod can allow voltage wise ?


Maestro

A LOT!!! Guess around 2.50V (not tried and verified =) but use this as a guideline:


BIOS Setting -> Translates into
-------------------------------------------
1.625V -> 2.060V
1.750V -> 2.240V


NB!!! be careful when you boot after doing the mod...if the BIOS is set at 1.85V you get something like 2.4V !!!!! could easily fry the chip....