What MODDED VDD are ppl running??

[Flymo]

I am going to to the VDD mod this week to see if I can get a few extra MHz on the FSB of this sucker

Currently running @ 12*200 stable in 3D (3D mark 2002 and 2003, and BF 1942)
I seem to have hit the ceiling with the CPU as above 2430 it craps out (low FSB and High multi to rule out FSB problems).

My current vdd is 1.58 V

In order to protect the board, I am planning to fit a resistor in series with the 15 turn 1K Ohm pot, so what I want to know is, what VDD do you guys recommend as the safe MAXIMUM VDD?

I was thinking along the lines of 1.95 V, so using the the following formula:

(176 / ohms resistance) + current vdd voltage = resulting vdd voltage

I would use a 476 Ohm resistor to limit the VDD to a MAXIMUM of 1.95 (actually a 470 Ohm to give 1.954 VDD).

Does this sound about right?
Or should I go for a max vdd of 2.0v or higher ??
At what point did you guys hit a ceiling ? (ie no extra fsb for extra vdd)

I already have the Mofsets heat-sinked and a 120mm Variable speed case fan blowing directly on to them.


Flymo

[Holst]

I dont get any higher FSB once I hit 1.8v VDD.

[Uncle Bob]

Here are some of my experiences I am at 1.82 as well and haven't tried more. A suggestion?
I soldered an old speaker (4 terminal with only wires on outside terminals) wire with a connector on it to these terminals:

http://8rda.com/upload/8rda_vdd_chip_mod2.jpg

What it allowed me to do was simply plug this:

http://8rda.com/upload/radioshack_pots.jpg

right into the connector. When I want to change the resistance, I remove it and do it off the board and don't risk frying the board. It is perfect for single setting resistors as well.

Just a suggestion!

On the soldering? Steady as she goes! It takes as small a wire as you can use. I found a speaker wire (app 20 AWG) worked great.

Happy modding! Let us hear how it turns out!

[Baba]

Ahh,
good to be registered at last, long time reader but never had the HW to discuss it...

anyway, I put a 1/2 watt 680ohm resistor using the same technique as Uncle Bob, and the VDD goes up to 1.84V. I haven't really stressed tested this but I am posting at 230.

[Uncle Bob]

Welcome, officially, of course!
Way to go! Is it stable?

[Baba]

thanks,

until i get better cooling, (2100+ AIUHB), its not prime 95 stable, but it is 3d mark stable.

dont know what that means, but without the mod, you have no chance of getting this high.

[herman]

i run @1.93 vdd.i found it gave me a 17 fsb increase over 1.85vdd.went from 210 stable in everything dual channel to 227 stable dual channel.every board seems to vary alot so see what is best for u and make sure u stick a good heatsink and fan on the NB.i put a stock amd heatsink on with a 60mm delta and it stays very cool.

http://service.futuremark.com/compare?2k1=6186231