To Voltage Mod or not to Voltage Mod...That's the Q... Abit KT7A-R

[AMDGuy]

My watercooled Duron 650 topped out at 952Mhz @ 1.85V. It runs at a cool 30C under normal operating conditions and 40C when fully stressed by Prime 95 Torture Test Priority 10. I'm confident it could bust 1000Mhz if I could get the voltage up to around 1.91V or so.

If anyone has detailed information on modding an Abit KT7A-R that they can share I'd appreciate it. I read about it at a couple of sites but they recommend an inline resistor. People here recommend "trimmers" be used instead. I'm still considering this mod and want to have the best information available. Does anyone know which IC chip on the Abit KT7A-R controls the voltage and which pins need to be modded? Tweakhardware.com recommends an inline resistor going to a transistor on the motherboard, but this is different than a post I read here about the KT7E.

Any help is greatly appreciated.

 

[n2]

hey!, sorry i can't really help with the vmod...
just curious tho,
are you sure it's worth the risk?
just a few more mhz isn't going to be hardly visible to ya...
and you have such a beautiful O/C and rig... to bump the vcore over 1.85 just seems like really pushing it lol.

maybe you want to torture it to the utmost maximum, and popping it gives you the perfect excuse for a 1.4gig Athlon?
i guess thats cool too.

i dunno, just my thoughts... good luck to you ,
and that poor little chip

 

[UnseenMenace]

Ohh well ignore this post.. I just gave you the Tweakhardware URL which you seem to be aware off sorry

 

[AMDGuy]

n2 (Jun 11, 2001 01:44 p.m.):
hey!, sorry i can't really help with the vmod...
just curious tho,
are you sure it's worth the risk?
just a few more mhz isn't going to be hardly visible to ya...
and you have such a beautiful O/C and rig... to bump the vcore over 1.85 just seems like really pushing it lol.

maybe you want to torture it to the utmost maximum, and popping it gives you the perfect excuse for a 1.4gig Athlon?
i guess thats cool too.

i dunno, just my thoughts... good luck to you ,
and that poor little chip

I'm still debating. I guess 1000Mhz is more a mental thing than a noticable performance thing. I was sure this chip would hit 1000Mhz. It was doing 800Mhz air cooled and 1.625 Volts. The temps are so cool I figured 1000Mhz would be easily attainable if not for the voltage limit. Ambient is 29.5C and CPU is 30C under normal operating conditions. It only went to 40C after about 45 min of Prime 95 and stayed at 40C for an hour.

I doubt I'll actually solder on the mainboard. I just wanted the info on hand in case I did get the guts down the road. Maybe when this is a backup system or something.

 

[n2]

i think those temps are awesome!!
and you seem to have a knack for overclocking...
probably quite likely you could pull it off, and get those bragging rights.
as far as soldering the resistor, that is rather easy. and it sounded like a good mod when i read that article over before...
to make it easier, get one of those magnifier lamps, the table clamp on type.
if you've soldered before, and have a bit of experience in knowing a cold solder from a proper joint.
i don't see a problem in store for you, just take your time.

 

[Colin]

AMDGuy - In response to your email, the chip is between the four caps, next to the toroid, just above the AGP slot. It's labled HIP6301CB. For those who have not seen my volt mod instructions, I will post them below. The pic will show the HIP6301CB. I will also add a pic of the trimmers mounted on a bread board as requested.

Solder wires to Pin 7 and Pin 10 of the IC that controls the voltage to the CPU. Put a 47K trimmer (49 cents at Radio Shack part # 271-283) between each wire and ground. Use a spade lug or loop under a motherboard mounting screw for your ground connection. For convenience I suggest you mount the trimmers on a piece of breadboard and secure it to your motherboard tray with Velcro.

Pin 7 controls the voltage, Pin 10 controls maximum voltage threshold. Turn the trimmers to full resistance boot your PC and start VIA Hardware Monitor. Set the polling interval to 2 seconds and slowly dial up the pin 7 trimmer until the voltage peaks. This should be about 2.1 volts. Then dial up the Pin 10 trimmer until your screen blanks and back it off a tad. Your PC will probably reboot when the screen blanks. Go back into VIA Hardware Monitor and dial the Pin 7 trimmer up to 2.3 volts. You may be able to go higher but I don’t recommend it.

Caution this will stress your cooling. Be careful or your CPU could end up a crispy critter. I also suggest buying a third hand device from Radio Shack to hold a pre-tinned wire to the IC leg while you solder. The magnifying glass on the third had will come in handy too. Get in and out fast so you don’t toast the IC. Lay off the caffeine and if you are of age, have a beer a half hour before soldering to steady your hands.

Be sure to tie your wires down to the board. After doing several boards, I finally screwed one up. The mod went fine but I snagged the wire to Pin 10 on the end of my workbench and ripped the IC pin right off the board.

[img="[URL]http://albums.photopoint.com/j/View?u=1551335&a=11768501&p=42534658[/URL]"]

Trimmers on breadboard.

[img="[URL]http://albums.photopoint.com/j/View?u=1551335&a=11768501&p=41984431[/URL]"]

The complete picture on my old KT7R.

[img="[URL]http://albums.photopoint.com/j/View?u=1551335&a=11768501&p=42534662[/URL]"]

 

[Colin]

One more thought on trimmers. Not all boards require the same amount of resistance. Some of the newer boards seem to require more. If you were to put too little resistance between ground and Pin 7, your computer would not boot. Using a trimmer allows you to dial in the resistance your board needs, and not what some well intended hardware Site author thought would apply to all motherboards.

 

[AMDGuy]

Colin (Jun 11, 2001 03:53 p.m.):
One more thought on trimmers. Not all boards require the same amount of resistance. Some of the newer boards seem to require more. If you were to put too little resistance between ground and Pin 7, your computer would not boot. Using a trimmer allows you to dial in the resistance your board needs, and not what some well intended hardware Site author thought would apply to all motherboards.

This is exactly what I needed. Thanks.
(now I just gotta get up the nerve to do it)

Have you noticed any negative side effects? Does this put stress on other board components?

 

[Colin]

One of my KT7-Rs died a mysterious death. It could be the volt mod but there is no conclusive evidence. Since a 1.2 gig Bird died first and the board failed when the Bird tried to post two times after the initial failure, I think this may point to something connected with the Bird. I have heard of other KT7s without the volt mod doing the same thing.