8800GT voltage mods

[scottc19]

It might be fixable, if nothing else was damaged. But having those resistors messed up might have caused other problems. You would have to remake the traces and put new resistors in that matched the old ones. This would be very delicate work... If you do give up on it let me know, Id be interested in it for parts and such.

[largon]

(...) The two resistors directly below the solder point (red) aren't there, and the resistor next to them (blue) may or may not be shot. It's reading 10ohms, is that normal? (...)

http://img503.imageshack.us/img503/9247/tarceua6rj2.jpg

It's definitely fixable. And it's fairly easy.
What you need to do is, is to desolder all those four surface mount resistors, then buy two 16Ω resistors (SMR or linear, it doesn't matter) and solder them in their place. Replace the "red" SMRs with one 16Ω resistor and the "blue" - and the one next to it on the right - with the other.

I did something like that for my own 8800GT.

[jason4207]

It's definitely fixable. And it's fairly easy.
What you need to do is, is to desolder all those four surface mount resistors, then buy two 16Ω resistors (SMR or linear, it doesn't matter) and solder them in their place. Replace the "red" SMRs with one 16Ω resistor and the "blue" - and the one next to it on the right - with the other.

I did something like that for my own 8800GT.

It might help to add something to the pic. Is this what you mean Largon? Are you supposed to bridge the far side (in relation to the Primarion) of those SMR's as shown?

Edit: And how do you type that Ohm symbol, Largon?

[alexio]

Will two 3.9k or 4.7k SMDs work well over these resistors for the OCP mod?

[jason4207]

Will two 3.9k or 4.7k SMDs work well over these resistors for the OCP mod?

Anything from 3.8-4.2 will work well. I'm sure the 4.7 would work also, but you won't get quite as much headroom.

You have it on the wrong spots, though. You need to solder them over the SMC'c adjacent to the SMRs you have circled. If you look back at a previous post of mine (592) you can see my pic of the OCP mod. I used 3.92k SMRs.

[Deluge]

It's definitely fixable. And it's fairly easy.
What you need to do is, is to desolder all those four surface mount resistors, then buy two 16Ω resistors (SMR or linear, it doesn't matter) and solder them in their place. Replace the "red" SMRs with one 16Ω resistor and the "blue" - and the one next to it on the right - with the other.

I did something like that for my own 8800GT.

So it would be like Jason's picture? How exactly would I attach the resistor, attach it to one point and then create a solder bridge to the other point? And one last question - before I lost the 'red' resistors I believe they read 400 something ohms, was that just a screwup on my part, or..?

Sorry for all the questions, and thanks very much for your help



@scott - I'll be sure to, I don't really want a $300 paperweight, though I have to admit, it would make a very attractive one

[jason4207]

Assuming my pic is correct (waiting on Largon) then you could just cut one leg of a standard resistor longer than the other, and use that to bridge the points.

Edit: Thinking about it some more...If you have to wire it as shown above then perhaps those points are already electrically the same point. You may not even have to worry about bridging it. Let's wait to see what Largon says, though.

[Deluge]

Alright, sounds good. Would you have any idea if 15 ohm resistors would work? I called the local radioshack and that's all they have.

[Nosfer@tu]

I only have 1,8K ohm and I dont think the succes rates for OVP mod are good.
So I take it 3.X would be best.

BUT DAMM the memory gets HOT

[scottc19]

I wish you luck! make sure when you do it, you use a magnifying glass(either while your doing it, or after to check each solder point after you make it) and take it slow, trying not to heat up the board too much. Also, what size wattage soldering iron are you using?

[Nosfer@tu]

I wish you luck! make sure when you do it, you use a magnifying glass(either while your doing it, or after to check each solder point after you make it) and take it slow, trying not to heat up the board too much. Also, what size wattage soldering iron are you using?

hehe thx for your concern

I have been doing vmodding since 04, so Im not afraid
My old school work
http://www.tweakup.dk/article/416/dk/

I my self find that a 50 watt variable soldering iron is the best.
and it is priced around 40 $.
I have used it for almost 3 years now.




And it is EXTREEMLY cheap

http://www.vellemanusa.com/us/enu/pr...iew/?id=522806

[Nosfer@tu]

How does the connection betwean the shader and Core clock work ?

Yesterday i spent a long time clocking all the way up to 800 Mhz core with the shader unlinked.

That dident work
Core dident rise above 74X mhx because the shader stayed at 1500 Mhz

I had old scematic for the levels of shader and GPU and how they where connected. But it dosent go above 750 Mhz core.

Can anyone explain this to me
Thx in advance

[os008]

Same here. To tell you the truth, i found the best performance to come from the Shader overclocked more than the ROPs. And to get the best gain overall, i just keep the Shaders between 2.5-2.6x of the ROPs, just my opinion and what i noticed, others might say something different!

What i want to say is, don't be concerned by that limitation, because you want them to be within the limit i just mentioned above .


EDIT: you might have noticed i didn't overclock the Shaders too much despite having the volt-mod in, and despite getting 65c at load now (managed to reduce it by 5 degrees 2 days ago). That's because i'm CPU bound, so getting it to 800/2000 won't give me a lot compared to the current clock, just more heat for nothing.

[Pacha]

I my self find that a 50 watt variable soldering iron is the best.
and it is priced around 40 $.
I have used it for almost 3 years now.




And it is EXTREEMLY cheap

the 30W iron I bought two years ago at the electronic store was priced 2.90€
THAT is EXTREMELY cheap


btw, can anyone tell me the diameter of the holes near the GPU? (in the corners) I guess it's between 2 and 3mm but I'd like to be sure

[jason4207]

I like that iron. I see it for less than $20 online. I may have to order it. What temp do you set it to? I've always just used a cheap RadioShack 15W.

To get your core over 756 you just need to increase your shader clock a little. Just a few steps. It won't by any means limit your max core OC if you turn up the shaders just a bit. I don't know why it does this, but it is an easy work-around.

[alexio]

I did the vMEM mod and at 1.95v loaded I can now do DDR2200+ 24/7 with 1.4ns Samsung timings (have Samsung chips on my card). I'll do the vGPU mod tomorrow and play a little with it. I'll really push it later on when I've bought tools for my Dremel to cut some old heatsinks to pieces.



Using an old stylograph and some silver glue I drew a line from one of the vMEM mod points. At the end of the line I made a little "pool" of silver glue by pushing the tip of the pen a little harder to the PCB. Then I hotglued the wire from the vRES in the right place making sure the exposed copper of the wire was dipping in the "pool" of silver glue. Afterwards I added another layer of glue to ensure proper conductivity of the connection.

I prefer silver glue over traditional soldering

[natedog420]

I did the vMEM mod and at 1.95v loaded I can now do DDR2200+ 24/7 with 1.4ns Samsung timings (have Samsung chips on my card). I'll do the vGPU mod tomorrow and play a little with it. I'll really push it later on when I've bought tools for my Dremel to cut some old heatsinks to pieces.



Using an old stylograph and some silver glue I drew a line from one of the vMEM mod points. At the end of the line I made a little "pool" of silver glue by pushing the tip of the pen a little harder to the PCB. Then I hotglued the wire from the vRES in the right place making sure the exposed copper of the wire was dipping in the "pool" of silver glue. Afterwards I added another layer of glue to ensure proper conductivity of the connection.

I prefer silver glue over traditional soldering

what the hell is that mod lol. please do tell what you just did. ty

[Nosfer@tu]

I like that iron. I see it for less than $20 online. I may have to order it. What temp do you set it to? I've always just used a cheap RadioShack 15W.

To get your core over 756 you just need to increase your shader clock a little. Just a few steps. It won't by any means limit your max core OC if you turn up the shaders just a bit. I don't know why it does this, but it is an easy work-around.

You should, we are attualy quite a few with it, and it has exchangable points 2.

I normaly set it at just above 65 % of max temp, But I have no problems using it at max = 50 Watt.

That is what I think you pay 150 $ for, the fact that the iron is hot on EVERY angle of the solder point. So somtimes if you need a specific angle of soldering you migth find it to cold and just turning it to maximum fixes that

I think I have done around 90-140 Vmods with this soldering iron.
Only I and Riska does comercial vmodding here in denmark. Not that I have that much work

Maybe once a month

I prefer silver glue over traditional soldering

Well using hot glue is somthing I strongly recommend NOT to.
How will you remove it? Just use sealstring or normal tape!

Hot glue is even more permanent than soldering

[alexio]

what the hell is that mod lol. please do tell what you just did. ty

Don't mind where the red wire ends (it has no purpose in mijn explanation, it just goes to one of the ground points on the PCB like it does normally). What I did is make the mods a little easier by diverting the solder points for the mods to an area on the PCB that isn't so crowded with components. I'm not sure if you can solder a wire to silver glue (although I think it's possible) but I used silver glue for connecting the wires.

Hot glue is even more permanent than soldering

Maybe my glue sticks are different than yours but I can easily remove a dot of this glue from a PCB (tried this on an old PCB before using it on the GT).

[natedog420]

could someone post a pic of the mod that lowers your memory voltage. i dont think ive seen that pic before. thanks

[Deluge]

Well, I attempted to save my GT, and it's not happening. The solder points are way too close together. I e-mailed XFX to ask if it's possible for them to fix it at my cost, but I kind of doubt they'd be able to - missing resistors and traces burnt from the rescue attempt, and all. What do you guys think? Maybe I'll just grab a cheapo eVGA for a while and step up when I have some cash.

@ Scott - PM me if you're still interested in it, I'm obviously not looking for too much.

[Asio]

scottc19,
I don't remember exactly but it was at something like: 900 / 2500 / 1100 when it died.

jason4207,
No visible evidence except that DMM reads GPU-2-GND resistance to be pretty much non-existant.

What voltages and mods do I need to get that far?
Did you just overclock it until it died or can this be used for 24/7 use.

Actually my pc wont be on for more then 5h a day most likely...

I plan to use a full body water block to cool gpu mem and mosfets...

[jae215]

could someone post a pic of the mod that lowers your memory voltage. i dont think ive seen that pic before. thanks

I would like to know this as well. A written explanation of the mod would work too. thanks buddies

[jason4207]

I would like to know this as well. A written explanation of the mod would work too. thanks buddies

Look at my post 592. I have taken a pic of it (vmem buck). 50k VR as shown. Viper John figured it out, and I just implemented it.

[Nosfer@tu]

Look at my post 592. I have taken a pic of it (vmem buck). 50k VR as shown. Viper John figured it out, and I just implemented it.

How much did it help you ?