Tbred Voltage Mod via Mobo Socket Jumpers

Is it possible to change the default voltage for an AMD XP/Tbred by putting wire jumpers between the Vcore pins in the motherboard socket, instead of cutting and connecting the bridges? This (adding the Vcore pin jumpers) is how you change the default voltage for the Intel Tualatin CPU's (for those that are familiar with this technique).

i havent seen no info on this.i guess what im saying is it is most likly possable to do but if i havent seen info on it. and i dont miss much on info.might try and search a few other forums if u cant find it here.

I found this Document on the AMD website. This document is for the AMD Athlon XP Processor Model 8. Is that the Thoroughbred processor?

If you look at Chapter 11, it details what all the pins are used for on the chip. If the Tbred is like the Intel Tualatin, you should be able to put a tiny wire between the various VID[4:0] pins and VSS (which is ground). This would functionally be the same as connecting the the bridges on the top side of the chip. To cut a bridge connection, you would have to either insulate the pin or cut the pin off (I admit that this is much harder to do).

FYI, in the voltage definition table, a 0 is a grounded pin (connected) and a 1 is a not grounded pin (cut).

given it a look see now,also i know exactly what your going after.i study some intel guides also

ill come back and edit this post with a reply.ill also see if i can put in touch with a person or persons who could help you somehow.

man 2 pages just of vcore pins.this way seems to be way harder than just hard coding it.plus you have some serous manhood to try this on a tbred.

here is a link to another forum incase you havent been there.some of the guys there are really into some heavy stuff and might have some additional helpfull info.

i dont have the guts to experiment like this on my 2200.
http://www.xtremesystems.org/forums/index.php?

If anyone was curious about whether this would work or not, I can tell you that it does work. I installed 2 small U-shaped pieces of wire between V3-VSS and V1-VSS last night. My default Vcore is now 1.75 volts, instead of 1.50 volts.

I can now select CPU voltages of up to 1.85 volts via the BIOS, whereas previously the limit was only 1.75 volts. I had expected to be able to select much higher voltages, but I guess the motherboard (KX7-333) somehow does not allow that (unless you do the motherboard volt mod).

If anyone wants to raise their default CPU voltage without having to cut and connect the bridges, this is another option.

Edward2...do you have a photo or diagram showing the pin locations?

its up top in his second post

Here is a LINK to the document on the AMD website regarding the Tbred chips. I could post a picture, but I don't think it would be large enough for you to be able to read the pins clearly.

The pin layout pictures are in Chapter 11. One picture shows the pin layout looking at the bottom of the chip. You would use this picture if you were going to connect a wire directly between the pins. The other picture shows the pin layout looking from the top of the chip, or looking at the socket itself. I used this picture to install the small U-shaped pieces of wire into the sockets.

WARNING: Disconnect your power supply before attempting this. Be very careful not to drop the wires when you are installing them, because obviously they could short out your motherboard if they are laying on the board when you boot up. I used needle-nosed pliers to hold the wires while I was installing them. Also, make sure that the wires are short enough and thin enough, so that your CPU will sit perfectly flat down in the socket. Otherwise, your heatsink will not make good contact with your CPU.

I have done this technique several times with my Intel Tualatin CPU's and with my new Tbred CPU in my sig, and I have never had a problem. Knock on wood!! You just need to take your time, make sure you have the right socket holes, and double check everything before you power up your computer.

Here is a closeup shot of the pins that I connected. On the Tbred A, V4-VSS and V0-VSS are already connected and V3/V2/V1 are not connected, which gives a default voltage of 1.500 volts. I connected V3-VSS and V1-VSS, which gives a default voltage of 1.750 volts.

awesome...I just found that and was about to post a similar photoshopped pic asking which ones you connected then I noticed the attach image option is gone hmmm...

I know what i'll be doing tomorrow, my TbredA 1700 has 1.5 default voltage too and my board doesn't a have voltage adjustment option without wacky mods

I'll update with my results tomorrow.

I think this thread deserves a sticky.

Couldn't wait till tomorrow..worked like a charm to 1.75V and temps are up about 4C

I passed a loop of 3d mark @150 FSB so now its time to run sandra and prime overnight and see what happens

I'm glad to hear that it worked for you, and that you were able to raise the FSB speed. Of course, it is to be expected that the CPU temp will increase with increased voltage, just make sure you have good cooling and you should be fine.

I think this technique will work well for people that don't want to or are afraid to modify the actual bridges on the chip. Also, this method does not permanently damage your chip if you later decide to sell the chip.

I'm using an AX7 for cooling so temps are still under 45C at 100% load. I've done this trick on several Intel chips using both the pin wrapping method and using u-shaped wires so it only took me about 20 mins. total.

sandra and prime both ran overnight with no probs

I should have figured out that you had done this before yourself. I'm glad to hear that your computer passed the stability testing.

This method just seems like a much easier technique than the "typical AMD approach", at least to me. Maybe I have just been around Intel chips for too long.

still 100% stable after 24 hour testing

thanks 4 the tip

cool it worked for me... i made this image to show where the pins are... i put them in the wrong place the first 2 times....

This is great info! It seems more reliable and reversible than painting on the cpu.

Ghost68, I see that you have the same CPU/mobo that I do. When I did this wire trick, the default voltage changed to 1.75, but I can only raise the voltage up to 1.85 via the BIOS. Did you have the same results? I have not tried adding the 3rd jumper between V2-VSS which would change the default voltage to 1.85. I don't know if this would open more voltage choices or not. I assume that it would probably not.

Also, what speeds (FSB/CPU/Multiplier) and voltage are you running? Were you able to increase your overclock after adding the jumpers?

Edward2 said:

Ghost68, I see that you have the same CPU/mobo that I do. When I did this wire trick, the default voltage changed to 1.75, but I can only raise the voltage up to 1.85 via the BIOS. Did you have the same results? I have not tried adding the 3rd jumper between V2-VSS which would change the default voltage to 1.85. I don't know if this would open more voltage choices or not. I assume that it would probably not.

Also, what speeds (FSB/CPU/Multiplier) and voltage are you running? Were you able to increase your overclock after adding the jumpers?

Click to expand...

yeah my max voltage is 1.85 volts (its the limit of the onboard voltage regulator) to get higher you have to do a volt mod ill get you a link in a sec...
now as far as my overclock im still testing... i was running at 1850mhz 185*10 i still cant get it past 1950mhz for the life of me... itl actually get into windows at 2ghz but as soon as i do anything processor intensive it hard locks.... at 1950 it wont get past the first few tests im prime95... so far its stable at 1.9ghz gonna try for 1.93 here in a min... i think im gonna have to volt mod this board after all.... ill update this with my highest oc as i go.... right now im calling it 1.9ghz...

FYI... I have not run Prime95 on mine, but it does run the Folding client 24/7 without any problems at the speeds in my sig. I can boot Windows at 2 GHz (11*182 and 10.5*191), but mine also locks up as soon as I do anything processor intensive.

I was surprised that raising the voltage to 1.85 did not seem to help the stability problems at 2 GHz, but I think my power supply may be running out of juice at that point. It is a 350w unit. The 5v rail gets down to about 4.70 volts.