Рalit 8600GTS Voltmods

People in this thread askin me for vmods on this card, so I publish it here:

Рalit 8600GTS Voltmods

Before you start voltmodding your Рalit 8600GTS, check the part number from back
side of the card. It must be "NE/86GTS+321-PM8884", if not - this voltmod may
not compatible with your card. May be this mod also can be done on both 256Mb
and 512Mb models, because PCB is the same, but not confirmed. I check it only
with 256Mb card.

Vgpu-mod

GPU voltage controlled by IC which marked as "BN-9B C06". It's located on back
side of the card, near of left upper corner. I can't define manufacturer of this
IC and can't find the datasheet, but it not necessary for do the mods...

I checked the PCB and located that pin 14 of "BN-9B C06" is feedback.
But pins of "BN-9B C06" is too small for soldering and you can use alternative
points, specified on this picture:

http://img123.imageshack.us/img123/3...vgpumodpv2.jpg

Vgpu-mod (soldering method): connect left side of the resistor marked as "Pencil Vgpu-mod"
to groung using 100k VR (set it to max resistance before do the mod).

Vgpu-mod (pencil method): just pencil the resistor marked as "Pencil Vgpu-mod".
Check resistance of this resistor using this table:

Rgpu <-> Vgpu
7.95k Ohm <-> 1.35V - nominal GPU voltage
7.55k Ohm <-> 1.43V
6.48k Ohm <-> 1.68V - optimal if you cooling good enough
6.03k Ohm <-> 1.80V - too much for this card

Be careful doing pencil Vgpu-mod on this card! Initial resistance (Rgpu) is too high.
Always check the resistance after shading the resistor!
Too much shading => too much GPU voltage => dead card.

Reverse Vgpu-mod (pencil method): you can descrease GPU voltage if you want - just pencil
the resistor marked as "Pencil reverse Vgpu-mod".

Vmem-mod

Memory voltage controller is Richtek RT9259A), located on back side of the card, left down corner.

http://img510.imageshack.us/img510/7...vmemmoddp9.jpg

Vmem-mod (soldering method): connect pin4 of RT9259A (Vmem-feedback)
and pin7 (ground) using 20k VR (set it to max resistance before do the mod).
Also you can use 10k VR for this mod if not have 20k one, but 20k is more suitable I think.

Vmem-mod (pencil method): just pencil the resistor marked as "Pencil mem-mod".
Check resistance of this resistor using this table:

Rmem <-> Vmem
324 Ohm <-> 2.09V - nominal memory voltage
299 Ohm <-> 2.25V
294 Ohm <-> 2.30V

Reverse Vmem-mod (pencil method): you can descrease memory voltage if you want - just pencil
the resistor marked as "Pencil reverse Vmem-mod".

Voltage measure points
Use legs of CP8 or CP4 capacitors (silver, 2.5V) for measure GPU voltage.
Use legs of CP9 or CP6 capacitors (green, 6.3V) for measure memory voltage.

PS. sorry for my english :rolleyes: