• Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.
  • The forums have been upgraded with support for dark mode. By default it will follow the setting on your system/browser. You may override it by scrolling to the end of the page and clicking the gears icon.

GeForce 8800 GS/GT/GTS Voltmods

Thanks for linking me to this thread Largon.

I bought the eVGA 9600GSO Dual Slot edition ($47 on newegg right now!!!), and so I'm going to go ahead and try this mod. Is it worth doing even if I'll be using the default dual slot cooler? Also, what variable resistors should I buy? I found these on radioshack (I could order from mouser, but with shipping it would be cheaper just to get them from radioshack)?

Errr...I'm guessing I'd need to order them on mouser.com or something. Radioshack doesn't carry resistors of the proper resistance for this.

Here are some resistors, would these work?

500 ohm potentiometer for GPU volt mod
http://www.mouser.com/Search/ProductDetail.aspx?qs=/zPWuUUsT7MBOUWHGrcugA==

20 Kohm potentiometer for memory volt mod
http://www.mouser.com/Search/ProductDetail.aspx?qs=m0BA540hBPd%2bnXSkPPJiaQ==

50 Kohm potentiometer for reverse voltage memory mod
http://www.mouser.com/Search/ProductDetail.aspx?qs=2jxZDUMdHjixhK9QkzGa9g==

4.7 Kohm potentiometer for OCP:
http://www.mouser.com/Search/ProductDetail.aspx?qs=3eDEvvxjZ0B2E6V7iiNcag==

OR (wasn't sure which to go with)

2.0 Kohm potentiometer for OCP:
http://www.mouser.com/Search/ProductDetail.aspx?qs=yLGXVRudD3ptg/FCghk3hw==

Thanks
 
Last edited:
Hi Largon,

Tell me, In stead of using this mod what do u think about using NiBiTor..? Because u can also change your voltage on NiBiTor.. Someone said that it does't work.. But why does my frame rate change when i adust the voltage in my bios with NiBitor..?
I'm no expert on this, so just want your opinion..

Thanks!
 
Is it worth doing even if I'll be using the default dual slot cooler?
The mods will definitely gain you some MHz. Especially for shader domain clock which gives the most significant performance gain.
this[/URL] for vGPU, this for vMEM and this for reverse vMEM. Note that reverse vMEM mod is useful only if your card has GDDR3 made by Qimonda. OCP mod is not needed unless you were using exotic cooling such as phase change, etc. If you absolutely insist on doing OCP too use this set at 4kΩ.

Before ordering the parts make sure your 9600GSO looks the same as in this guide.

How much of an oc could I probably get with the dual-slot air cooler? What cooler should I buy to replace it if I want better results (would it be worth it to replace the cooler?)?
Sorry, my knowledge of GPU air cooling is very limited as I've been watercooling my GPUs for years now.
:ohwell: :)
quadomatic said:
900/1135/2250 would probably be pushing it on air, huh?
I think it's rather safe to say 900MHz core and 2250MHz shaders gaming stable are not going to happen on air cooling. Even on water it would require a lucky card.
quadomatic said:
Someone said this on newegg about the card:
Low stock fan speed and high temps. Idle was around 55C, load at 75C with stock clocks. At 700/1500/1000 with fans at 100%, 53C load temp.
Is that good or bad?
700/1500/1000 should be perfectly doable on stock air and stock voltages. Infact, I'd expect a couple hundred MHz more than 1500MHz for the shader OC on stock cooling & stock volts. ;)

Tell me, In stead of using this mod what do u think about using NiBiTor..? Because u can also change your voltage on NiBiTor..
As far as I know, the maximum voltage one can get via a BIOS mod is 1.15v.
jeanpieterse said:
Someone said that it does't work.. But why does my frame rate change when i adust the voltage in my bios with NiBitor..?
Changing the voltage does not by itself increase the performance thus any change in fps cannot be due to any voltage tweaks one does into the card's BIOS.
 
Thanks a bunch largon! I'll be looking into this then once I get my card.
 
Thanks a bunch largon! I'll be looking into this then once I get my card.
FYI, the EVGA 9600GSO Dual Slot has a different PCB design/layout than the single slot 8800GS/9600GSO. IMHO, it is a slightly weaker design/performance.
 
FYI, the EVGA 9600GSO Dual Slot has a different PCB design/layout than the single slot 8800GS/9600GSO. IMHO, it is a slightly weaker design/performance.

Crap...does that mean I won't be able to volt mod it? Or that I would have to figure out how to (might as well mean I can't...or maybe I could)?
 
Crap...does that mean I won't be able to volt mod it? Or that I would have to figure out how to (might as well mean I can't...or maybe I could)?

just take the cooler off and take some naked pics of it like I did on the Palit 9600 GSO thread those are my pics if you didnt know, largon know his stuff ;)
 
Crap...does that mean I won't be able to volt mod it? Or that I would have to figure out how to (might as well mean I can't...or maybe I could)?
I have 2x 9600GSO dual slot's folding 24/7 and they score about 5-10% lower than the 8800GS. If there is a volt mod that would help the shader output, I'm onboard! I just ordered 2 more 9600GSO single slot's, as they are identical PCB to the 8800GS, thus better performance.
 
I have 2x 9600GSO dual slot's folding 24/7 and they score about 5-10% lower than the 8800GS. If there is a volt mod that would help the shader output, I'm onboard! I just ordered 2 more 9600GSO single slot's, as they are identical PCB to the 8800GS, thus better performance.
yes there should be a volt mod just post some pics for largon he should know what you need to do

cuz the shaders run off the core volts

I was getting like 6-7k with one card but im never on vista that much so thats why i havent folded in a while :o
 
just take the cooler off and take some naked pics of it like I did on the Palit 9600 GSO thread those are my pics if you didnt know, largon know his stuff ;)

Cool. I probably won't receive the card till some time next week though (paid newegg by money order, proly will end up shipping by monday or tuesday next week, so i'd get it by next friday). If pictures haven't been posted by then I'll try taking the cooler off. Hopefully it's not an incredibly difficult task to put take off and put back on. It wasn't real difficult with my X850 Pro, but then, that wasn't a dual slot cooler.

Despite all the relatively risky (while actually not very risky at all) modding I've done with my current system, it seems to have paid off fairly well (Pentium Dual Core E2200+fsb locked motherboard+2GB Ram+HyperTX 2 Cooler for less than $100, cpu overclocked to 3Ghz by BSEL and vCore mod). This will be a nice cheap addition, proving that you can in fact play games on a computer well for very, very cheap.

If I can handle Grand Theft Auto IV in November on my system with high settings, no AA at 1280x1024, I will be incredibly pleased.
 
My 9600GSO is supposed to come in this Thursday. I'll try to get pictures posted then.
 
Hey all, life has been fairly busy, and I was a bit fearful of taking off the cooler from my dual-slot eVGA 9600GSO. But, since I don't have a whole lot of time for gaming at this very moment (hopefully that'll change soon) I pulled my 9600GSO from my computer to take the cooler off and take some pictures. I'm running on my Intel integrated GMA950 right now...yikes.

I tried to take as good pics as I could. The images are fairly high resolution (3072x2304), and in total all the pictures weigh in at almost 20MB, so I zipped them up and uploaded them to filedropper.

It seems like I could overclock this card quite a bit. Without the volt mod, it runs at 752 mhz core/1806 mhz shader/1050 mhz memory. When I took the cooler off I found that the memory chips are Samsung, not the qimonda chips that were mentioned as being questionable earlier (though I don't know anything about the Samsung chips).

For $34, it definitely seems like I'm getting my money's worth. Fallout 3 runs beautifully, as does most every other game I've tried (Crysis is a bit questionable, but that's to be expected).

So, if someone could have a look at these pictures and tell me what I can do for a volt mod, I'd appreciate it:

http://www.filedropper.com/9600gso

Thanks a bunch!
 
So...has anyone taken a look?
 
Ummm, yeah...

The reason I posted the pictures is because the eVGA card doesn't have the same PCB layout as any of the other cards out there, which is why I needed someone to look at the pictures I posted of my card.

Since my card has been sitting outside of my PC for about a week, and I've been using my integrated intel chipset for vga, if I thought finding a solution was as easy as Google, I would've found it already.
 
Ok, my bad.

Lemme take a look. The voltage control chips should be pretty much the same.

edit: your link doesn't work :(
 
Ok, my bad.

Lemme take a look. The voltage control chips should be pretty much the same.

edit: your link doesn't work :(

DARNIT

I'll find a better host.
 
There, they've been uploaded to Imageshack...I had to reduce quality of the images from 89 to 85 in GIMP though.

I do wonder if the "N88GT-LF REV: 1.2" printed on the front of the PCB would help at all.

Back:



Zoomed (Left, Center, Right):


Front:



Zoomed (Left, Center, Right):

 
Last edited:
Interesting lay-out.

The voltage control chip (for the gpu at least) is the RT8802A chip on the front-right of the board.

http://www.alldatasheet.com/datasheet-pdf/pdf/207883/RICHTEK/RT8802A.html

I'll have a quick look through the datasheet, but it's been a long time since i did electronics at college. Anyone feel free to jump in if you figure it out.

EDIT:

If you have a conductive pen you could do a VID voltmod which would be quicker and easier than using a pot. See pages 5-6 for the VID voltage table. Basically you set the gpu voltage by removing SMR's and bridging gaps.

Capture002109.jpg
Capture001846.jpg
 
Last edited:
infrared:

Thanks for taking a look. I really appreciate it.

If anyone needs better pictures of any specific part of the pcb, let me know.
 
Hmmm, I don't really know what the VID-Table says. Is it just that if there's resistance on some pins and none on others then the voltage will be different? So, I'd match up the resistor placement with the 0's being no resistor, 1's meaning yes there's a resistor, and the output at the end of the chart is the voltage I'd get?

If I took too high of a voltage, then wouldn't I be kinda screwed since I wouldn't be able to put the resistors back?

WOW, the picture makes those soldering points look big. Those resistors are absolutely tiny. I'm not sure how I'd go about removing those.

Just as a size comparison, I put a penny next to the chip. Those points are TINY.

 
Last edited:
You've got it. They basically ground out the pin, which would be a 0 on the VID table. If we can find a vmeasure point for the vgpu we can verify that.

To remove them you can heat them with a soldering iron while lifting them with a fine pair of tweezers. I used to just crush them with needle-nose pliers lol. Use conductive ink to re-connect the pads. To make it more permanent when you have the desired voltage you can spray over the area with a conformal coating to protect it. Comes in an aerosol can you can get at any electrical shop.

Ok, working from the table, if you 'open' the connection (1), the effect would be:

VID 6 = +0.00625
VID 5 = -0.01250
VID 4 = -0.40000
VID 3 = -0.20000
VID 2 = -0.10000
VID 1 = -0.05000
VID 0 = -0.02500


Hmm, I'll drop Solaris17 a PM. He should be able to help figure out a bit more.

I'm off for the night (3:10am here lol). I'll take another look tomorow after work. Hopefully we can figure out a Vmeasure point, and then maybe the vmod for the memory.
 
Last edited:
Cool, sounds good.

Just to check, how are we able to tell which side of the chip is facing "up", so we know which pins are the vid pins?

Also let me know if you need me to read off the names on any other chips. I notice the names on the ones on the back aren't that visible.
 
Last edited:
Back
Top