x1900 alternate GPU voltmod

[mandelore]

Hi all, this is really just an addition to Wizzards x1900 series voltmod guide, aimed mainly at people who want to increase gpu core voltage but are unable to easily remove their card from their system due to either custom cooling or extensive watercooling etc etc.

Basically this is the same mod, but done on the back side of the x1900 pcb. this would enable it to be done much more easily without needing to remove the card from your cooling devices.

I have traced the solder points that Wizzards guide highlights and found other appropriate solder points too. I have included some pics and a full pcb pic to indicate the area im discussing.

http://i22.photobucket.com/albums/b312/eve_images/x1900voltmod22.jpg
This photo basically shows which side of the pcb im working with, which is quite accessible, the side with the power connector.

http://i22.photobucket.com/albums/b312/eve_images/x1900voltmod.jpg
This photo shows (black marker pen) the two points to connect, there is a small hole at the bottom right of the IC shown at the bottom of the pic, and an arrow tracing to the connector for the voltage regulator push pins, this is GROUND. So, all that needs doing, is connecting a 50K ohm variable resistor/potentiometer between these two points, and will also allow adjustment while in the case and connected to the motherboard with the resistor being positioned on the upwards facing back of the pcb.

Also, note the circled scratched area to the right of the circled solder point, this, once the surface is gently scraped away is also ground, but obviously is riskier to to than simply soldering at the ground shown on the photo.

Anyways, hope this info helps and remember, any mods you do, you take responsibility for, im not forcing you to do anything :p

Mand

[largon]

That point seem quite hard to solder on. It's smaller than the pads on the frontside and there's no preapplied solder.

There are several grounds nearby where soldering would be easier than the one around vreg heatsink push pins as there's no preapplied solder there.
For example the PCIe 12V plug grounds would be very easy to ground the vr. And then there's the empty R3030 pad on the far right in your pic. Or pin#11 on PM58AC.

[mandelore]

true there are other grounds that can be soldered to, and as for the small solder point, if you have any skill at soldering (which u better if ur even attemping any voltmods) it isnt difficult at all, even a tiny solder coated wire partially inserted into the hole and heated will apply quantities of solder. All you need is a steady hand, a good soldering iron and some patience. I personally have soldered far more difficult things, and even resorted to bonding a needle to a soldering tip for extra precision.


Edit: a tip: lay the wire you are going to solder on the pcb silkscreen with the end resting on the solder point. Tape the wire to keep is still, with the wire tip on the solder point, without u needing to hold it, this makes it very easy to apply a small amount of solder and make a successful bond.