8800s OVP Mod ......

[dinos22]

Higher GPU clocks

i meant electronics wise

is that part of the OVP mod?

[T_M]

SO I think that this is the cause to work properly the OVP Mod.....One resistor is the "start up" voltage and the other resistors "tracks" the "spikes" during runing.....So if a "spike" of Core Voltage is high, the VGA powers down.....
During Vdroop (running a 3D), the VGPU NOT only goes down BUT produces HIGH "spikes" as well during a "relaxed scene" of the 3D.....
That's the reason that it worked perfect for me......

solder extra coils in parallel with the existing ones so to avoid the BIG Vdroop of it and then test it in real?.....
ONLY thing you need, is to unsolder some coils from an old motherboard and then solder them onto the VGA with a lot of heatage on the soldering iron.....

For anyone interested in performing hipro's vGPU smoothing mods, here's a confirmed correct diagram of how to achieve it

http://img.photobucket.com/albums/v3...scan-front.jpg

The caps need to be electrolytic 1500, 2200 or 3300 uF with the '-' terminal on the ground side of the SMD cap, and the '+' terminal on the vGPU side.

The coils should be from an old mobo and just soldered across the existing ones.

Just incase you missed it.
It seems it should be performed in conjuction with the OVP mod to gain any real benefits.

[dinos22]

cool

[hipro5]

T_M I think that these coils are a bit HIGH in uH.... and LOW in current...
Also are these caps with low ESR or you just bought what this shop had?....
Why don't you try what I've told you?.....Find an old motherboard and unsolder them...There you will definatelly find HIGH current coils with low uHs and LOW ESR caps....

[T_M]

Because here in Singapore an "old" mobo costs ~USD$40, and all my dead/surplus boards use solids.
Guess i'll just have to go on an old/dead mobo hunt....

How can you tell about the chokes being high in uH, is it the wire thickness?

[hipro5]

Find an old ABIT IC7 or ASUS P4C800 series......They are GOOD....PLUS IC7 has the BEST Electrolytic caps Rubicom.....

Chokes (Coils) MUST be a bit bigher then the ones you have and MUST have THREE coils in parallel rounded on the ferrite core (about 5 - 6 rounds).....

[T_M]

Oh i see now, when i look back at your picture.
Its 3 wires that are looped on yours. OK mate i'll keep looking.

[T_M]

Will these do the trick?
Pretty sure its what im after so ill start harvesting.

[hipro5]

They are just........PERFECT.......

[T_M]

Awesome, any tips then on how to remove them?
I know i need a lot of heat, but what technique?
Heat the underside or the topside?

[T_M]

Wow, that was easier than i thought it would be.
60W soldering iron and a little gentle persuasion:

[hipro5]

Heh, heh, heh......You're moving perfect....

[T_M]

I wouldnt call my soldering skills perfect, i had a hard time getting the solder to stick to the existing inductors, but i think i've managed:





Looks like my Ultra has two dicks hehehe

[T_M]

The card is now running on water, no problems there but im still seeing 0.05V+ vdroop in ATItool, and 0.38V at worst point in Firefly '06.

[N1ck R1mer]

http://www.xtremesystems.org/forums/...&postcount=276
Anymore info from anyone, or has everyone just gone into the main thread?

Absolutely the same thing with my Leadtek 8800GTS - OVP Mod is NOT WORKING with GTS
Replacing the 70b resistor with 4,7 KOhm lowers Vgpu, and after adjusting it to the same level (1,45 Vgpu (2D)) it causes blank screen in HL2 Episode Two again with Vgpu drop to 0.

my dfi p965 has the primarion 3539!!!I've searched a little and found another datasheet from other company which makes the excact same chip and i have the full datasheet from that!3539 has a pin named vr_ready and i came in conclusion that this must controll the vdroop!!

If you have 3539 datasheet, please post it!

[hipro5]

The card is now running on water, no problems there but im still seeing 0.05V+ vdroop in ATItool, and 0.38V at worst point in Firefly '06.

Measure with a multimeter to be sure after on the coils you have soldered and on the side of them which is to the Core....
Also do the OVP Mod....

Next time when soldering, use some soldering paste to "smooth" your solderings....

[T_M]

Just measured each coil on the core side, and from bottom to top i read:
1.628V, 1.625V, 1.615V, 1.615V

My vCore read point on back of card reads: 1.615V

Will attach my OVP mod and see if there is a change to droop.
BTW my droop is 0.08V in 3d01!

[T_M]

Having a lot of troubles with driver corruptions and such, but as far as i can tell so far, when i connect the OVP ground i end up with vdrop (not droop) of about 0.1V.
Is that supposed to happen?

Note that i still cannot get 5.1K on the OVP resistor.
As soon as i trim down past about 5.8K it will suddenly jump to 4.2K and keep going down.

[hipro5]

Leave it at 4.2K and test it there to see how it will react....

[T_M]

But do you think it's safe to operate if i'm seeing such a large vdrop (not droop)?

[Alexxx650]

dinos22 & hipro5 & T_M
All show the drawings a drawing, on which 4 capacitors, but beside all cost stand whole 2. why?
That will give if put only 4 capacitors? value has not found.

[T_M]

I only put 2 capacitors because thats what Hipro did.
If it will help, i can solder on 2 more.

Here's Hipro's: http://www.hipro-tech.com/images/hip...800Ultra_moded

[Hazaro]

I only put 2 capacitors because thats what Hipro did.
If it will help, i can solder on 2 more.

Here's Hipro's: http://www.hipro-tech.com/images/hip...800Ultra_moded

Forgot your .jpg ending

http://www.hipro-tech.com/images/hip...ltra_moded.jpg

[hipro5]

I only put 2 capacitors because thats what Hipro did.
If it will help, i can solder on 2 more.

Here's Hipro's: http://www.hipro-tech.com/images/hip...800Ultra_moded

DID you put HEATSINKS ON VGPU's tiny Mos-Fets?.....Coz the hoter they get, their charasteristics change......Heatsinks ON them, is a MUST.....

IF you play with subzero, you don't need heatsinks on ram chips (better put on them too but not that much needed) BUT on the Power Mos-Fets you deffinately NEED....

[Alexxx650]

Want to put only 4 capacitors. I this will help? Or no?