7800GTX overclocks with Volt Mods??

[Malves]

Nice, man! Good job!

[Kinc]

Wtg!

Heared that the vcore mod requires you to remove a few SMD parts? You think there is a safer way around that?

[persivore]

Good work on the Vdd mod . Does the card need Vddq or Vref as well?

Can someone check the voltages at pins 12, 23, 24, 26, 27 and 28. I'm looking for a voltage of about 0.8v (or alternatively the voltage which is set with the VID pins) on one of those pins, which should be the internal reference voltage for the regulator, which should be present on the feedback pin for the regulator.

[ViperJohn]

Very nice... well done
Only Vcore is missing to make me completely happy - on vrzone a guy reached with a vcore mod 630 mhz on air... :-/

That is Jason57. We have emailed a couple of time. The card did a tad over 11k on dry ice. It appears to be an exceptionally good card but there isn't enoygh data yet to know what are going to be poor, average, good and "oh my god" cards yet in the luck of the draw.

Viper

[Malves]

Here's the VDD mod done by ViperJohn. Thanx for the pics, man. 100k trimmer, lower resistance for more volts.

[VoRtAn_MaDgE]

Nicely done ViperJohn, clean and very professional as always...

Did u have time to test the mod?

Any gains in mhz on the mem's? Any idea about the max but safe voltage to apply on memories? Depends on the cooling of course...extreme cooling will freeze the pcb of the card allowing more volts i presume!

Is there a vcore on the way? I ask that cuzz it's obvious that there are people that already know it.

Thks for the effort once again

[Malves]

Is there a vcore on the way? I ask that cuzz it's obvious that there are people that already know it.

Ppl that already know it, won't tell you or us. That's why we are here. We just gave you guys the VDD mod, now you gonna have to wait for the vGPU mod.
You guys can help by providing the information persivore asked, if any of you have the card in hands.

[VoRtAn_MaDgE]

I have the cards in my hands but i will be off the weekend (tuning show in portugal, international ) i will start digging in pdf's after that, if u need some photos of any specific area just tell me, i will try to get a digi cam to take some real close macro shots...

edit: show me the places to measure volts

[VoRtAn_MaDgE]

For what i search already this is the multiphase controller that will allow us to change vcore, correct me if i'm wrong...



I assume that persivore is asking about the pins values of the pic i posted above am i correct???

This pdf is one of the most or maybe the most imcompleted pdf from this nature that i found on the web...

I will try to arrive this night home soon to check the voltages guys!

[Malves]

These are the points that he asked.

[VoRtAn_MaDgE]

Thks for the pic Malves will help a lot...

But in my case its very hard to check the voltages on that spot cuzz my mobo is in the case, and the mobo attached to the prommy ...

The place is this one...sorry for the quality but just to see how hard is to measure voltage in this situation, legs of the pins are real close and like this is hard to check one without touching others



Going try to check in other vga maybe

[Malves]

Attach a needle with eletrical tape to the lead of your MM.

[VoRtAn_MaDgE]

Needle needed , got to find one...

btw malves, vdd measurement point is where... ???

[Malves]

Good thing you asked. See if you can find it here...

http://www.malvescorner.net/7800.html

I wanna see if ppl can understand that pic.

[VoRtAn_MaDgE]

vdd, pin24 - 3,52v checked...

got to see if i can check the others, dunno where my brother put the electrical tape grrr

[VoRtAn_MaDgE]

Good thing you asked. See if you can find it here...

http://www.malvescorner.net/7800.html

I wanna see if ppl can understand that pic.

Tha't too easy Malves ... just need to find c610, next to the label 2,09v default checked

[harleybro]

Attach a needle with eletrical tape to the lead of your MM.

Love that idea and never though of it. Had problems last time I was checking a chip upside down and on the other side of my card. Malves that is an excellant diagram you have on your site very easy to understand. I can't read mine till Tuesday so if nothing by then I'll get all the readings you need. Lettin someone borrow it for the weekend to pull off some SLI runs.

[ViperJohn]

These are the points that he asked.

Pin 23 (V12_SEN) which is the left pin of the two pins indicated in red along the bottom side of the chip has a voltage divider

If you follow straight down from P23 the SMR just below the automated test point pad goes to Vcore PS B+ out. The SMR marked 622 to the left goes to ground and forms the other 1/2 of the divider. I tried a Vmod at the 622 SMR already.

I started 100k then turned down to 50K and the Vcore did not change even 1/1000 of a volt so that isn't da place. Someone can double check me on that if they want.

The three Vdd input pins (12, 24 ans 36) look like are they are traced to each other under the chip from the ohm meter readings of zero ohms to each other.

Viper

[ViperJohn]

This pdf is one of the most or maybe the most imcompleted pdf from this nature that i found on the web.

Yeah the PDF for the ISL6592 is about as useless as it can get with only a pin out and no functional descriptions.

Viper

[persivore]

check out this datasheet: http://www.intersil.com/data/fn/fn9157.pdf . It contains a reference circuit digram for the ISL6592, so it should be possible to work out a mod from that. It looks like Vsenp (pin 26) is connected as feedback, but it doesn't look like there is a resistor divider on the reference design, so a cut-trace might be needed to do the mod, depending on how closely the manufacturers have followed the design.

Edit: It looks like there is also a possible OCP mod by connecting a VR between pin 38 (cal_cur_sen) and ground. I don't know if one will be needed tho

[ViperJohn]

check out this datasheet: http://www.intersil.com/data/fn/fn9157.pdf . It contains a reference circuit digram for the ISL6592, so it should be possible to work out a mod from that. It looks like Vsenp (pin 26) is connected as feedback, but it doesn't look like there is a resistor divider on the reference design, so a cut-trace might be needed to do the mod, depending on how closely the manufacturers have followed the design.

Edit: It looks like there is also a possible OCP mod by connecting a VR between pin 38 (cal_cur_sen) and ground. I don't know if one will be needed tho

Good find.

Here are the PSENN and PSENP as built circuits on the 7800. Possibility of
adding a 3 wire divider trimmer here.

Viper

[Chr0n1c]

From MickeyMouse:

Solder a 15turn"multi turn" 250 ohm vr or 2 1k vr's in par. to these two points. "do not exceed a 500ohm vr as jumps are too great". the resistor is the circuit the solder pad is ground so feel free to use another ground instead of this tiny tiny solder pad..

7800vcore
http://img93.imageshack.us/img93/499/7800vgpu9nq.jpg

7800vcore mod area and read point
http://img36.imageshack.us/img36/4726/7800corea0kt.jpg

[symbolized?]

What the hell - is this mod working? And where are the cutted traces and remoced smd parts? oO

[Chr0n1c]

http://service.futuremark.com/compare?2k3=4089232
http://service.futuremark.com/compare?3dm05=987646

The mod is from the guy that did those, idk about you but I'm not about to question it. They are legit, he wouldn't share them with me if otherwise.

[VoRtAn_MaDgE]

I am working but i'm seeing that u guys have a lot of new info about this thread... got to check it better when arrive home?
Is the vgpu working?