8800GTS 512Mb (G92) vMods

[Bail_w]

I like to use this website to search: http://www.alliedelec.com/

I like the way they show a pic while you search...makes it easier. But, I've heard they have a minimum purchase of like $25, but I can't confirm this.

Then you just take the part number and plug it into Mouser to get what you want.

Here's a list off of Allied: http://www.alliedelec.com/Catalog/In...513+4294912030

Just pick one that looks like it'll work best w/ the way you want to mount the device on the board.

Thanks.

[andrew2004gto]

ok idk what i can do my volts for the core is 1.35, and i try to raise it and i locks up and restarts and if i set my core above 828 it will lock up in a game like crysis and the screen will shake of the image and stays like that and usually i have to restart, i dont think its my temps they never go about 70C and i know its not the power supply or cpu or motherboard all brand new cept this card and does the same thing on my old system

[STEvil]

You need to keep temps lower to clock well. 70c is too high. If I run my fan at 100% I can do 850 at 1.35v idle (~1.4v load) but using the stock fan profile I am limited to 800 @ 1.25v idle (~1.29v load).

[BenchZowner]

Got a friends' card here doing 918MHz AquaMark 3 with the stock cooler ( 100% fan cycle duty ) [ maybe it can clock even higher, I'm not done with it yet ]

Can't wait to put this one on LN2

[bobbobson]

Got a friends' card here doing 918MHz AquaMark 3 with the stock cooler ( 100% fan cycle duty ) [ maybe it can clock even higher, I'm not done with it yet ]

Can't wait to put this one on LN2

Where did you say you lived again ?

I'll be picking up my new GTS on the weekend. Any brands that are known to have more samsung then others ? Cheers

[BenchZowner]

This one's eVGA ( standard one, not pre-overclocked edition )
But I think that it's using Qimonda GDDR3 not Samsung ( I'll remove the heatsink tomorrow to make sure ).

[largon]

BenchZowner,
At what vGPU was that 918MHz AM3 done? Tried how high the shaders go by themselves? Anyways, that's a golden card.

[BenchZowner]

Clocks are:
918MHz GPU Core
2052MHz SPs
999MHz RAM ( Didn't test the ram yet, so I'm using a "safe" freq )

Vgpu @ 1.468V

P.S. Shader testing ( at lower voltage though ) had the shaders bench AQ3 at 2268MHz [ with the core @ 828MHz if I recall correctly ]

[cole2109]

1.468V on AIR
Idle or Load voltage?

[BenchZowner]

1.468V on AIR

Make it on...stock cooler

Idle or Load voltage?

Load.

[Bail_w]

lol are you kidding me? btw, you have to go to the services section and not here.

[ericab]

hey all, im gonna try to do this mod tommorow on my brand new bfg 8800gts (g92).

so; are these the trimmers i need??

500 ohm
http://tinyurl.com/2dnujo

1k ohm (for Vmem i suppose?)
http://tinyurl.com/23pm6l


all products are from jameco

[largon]

ericab,
500Ω is perfect for the vGPU mod but that 1kΩ is useless for vMEM, if you'd use that for vMEM your mem chips would die the instant you turn your computer on after soldering the VR. Stick with a VR rated to 20-50kΩ.

[ericab]

once i have the mod completed; before i turn on the power to the computer; what position should the trimmers knob be in? should i turn it all the way to the left ? to the right ? middle ?

[Zeus]

Measure the resistance before you solder them, you must set them to max resistance.

Make sure to solder to the right outer leg, once you set max resistance between the middle and one of the outer legs, resistance between the middle and the other outer leg will be 0 ohm and your card will be fried.

It's best to cut one of the outer legs of to avoid mistakes.

[ghost_recon88]

I just gathered all the necessary resistors to do this mod, but I had the hardest time finding a 50k variable resistor for the RAM, and instead had to settle with a 100k. Is that ok, or is it gonna screw with the voltages too much? Thanks.

[ericab]

well...
i did it, i took the plunge... with terrible results.

well, maybe not that bad, seeing that my card still works, but it simply would NOT work with all the connections made...
i would power on the computer, and my monitors wouldnt turn on.
also, with the voltage testing spot, i got no reading whatsoever. (see attached pics)

ive since unsoldered them, and am using the card right now...(seems to work just fine still)
i have no clue what went wrong, can someone help me?

i took some pictures of it before i unsoldered the connections...

(yes; i know my soldering, wire organization, and pictures blow )

images:

variable resistor used:


voltage test point:


bad angle:


resistor w/connections:


connections to the on/off switch:


another on/off switch pic:

[largon]

First of all, your vGPU measuring point is on the wrong side of the capacitor - ground that is. Secondly, your VR is a single turn, always use a multiturn resistor for vmodding.

What comes to the actual issue...
Your vMEM measurement point looks shorted.

[ericab]

First of all, your vGPU measuring point is on the wrong side of the capacitor - ground that is. Secondly, your VR is a single turn, always use a multiturn resistor for vmodding.

What comes to the actual issue...
Your vMEM measurement point looks shorted.

ohhhhhh... ok, i wasn't thinking about what side of the cap needs to be soldered to..

ok, so, as for the VR; i had one hell of a time finding a 500ohm multi turn...

i purchased an alternate one just in case luckily.
will this one:

work ?

as for the vmem being shorted; why do you say so?

aside from all of that, did everything look like it should be working ?


*EDIT*

1 last thing..
when it comes to this picture:
http://img.photobucket.com/albums/v3...0GTS-vMods.jpg
where is says "vGPU = 1K VR" and has a red arrow pointing to the little dot... how CRITICAL is it the solder is perfectly on that one spot? i only ask because it is SO SMALL its damn near impossible for me to get it done well. is there an alternate way to get a wire coming from there ? theres simply no working room...

*EDIT2*
how much heat from my soldering gun can these capacitors take ? it seems hard to get the solder to stick to them without holding the soldering gun on them for a few seconds while the solder melts.

[jason4207]

Try one of these VR's.

http://www.alliedelec.com/Catalog/In...513+4294912030

[ericab]

Try one of these VR's.

http://www.alliedelec.com/Catalog/In...513+4294912030

but will this work ?


*EDIT*

shi*, it looks like you were right. one of those tiny capacitors just fell off.
the farthest left capacitor in the read vGPU...
now what the hell do i do ? (the cards still working... )

[largon]

The fallen cap isn't "needed" as there's a multitude of the same caps parallel to it. It wouldn't hurt to solder it back in though.

ohhhhhh... ok, i wasn't thinking about what side of the cap needs to be soldered to..

Caps are "always" connected to one pole to a ground and the other to live voltage. Your measuring point was on the ground pole.

will this one:

work ?

If it's a multiturn and rated to 500Ω (as it appears) - it's good. Though, the metallic casing is a bit prolematic - you'd need to insulate the whole thing so that it doesn't short things. Those linked by jason4207 would be perfect.

as for the vmem being shorted; why do you say so?

It looks like the measuring-wire with it's blob of solder connects both ends of the capacitor.

1 last thing..
when it comes to this picture:
http://img.photobucket.com/albums/v3...0GTS-vMods.jpg
where is says "vGPU = 1K VR" and has a red arrow pointing to the little dot... how CRITICAL is it the solder is perfectly on that one spot? i only ask because it is SO SMALL its damn near impossible for me to get it done well. is there an alternate way to get a wire coming from there ? theres simply no working room...

There's only 4 places you can solder:
http://img227.imageshack.us/img227/3...vmemmodgx6.jpg (see "optional soldering points")

how much heat from my soldering gun can these capacitors take ? it seems hard to get the solder to stick to them without holding the soldering gun on them for a few seconds while the solder melts.

SMDs are sensitive but you should be able solder on them as long as the heating only takes max ~5 seconds. Btw, there might be a sort of lacquer on some components, you might want to scrape the place you're going to solder with a sharp blade before poking it with the iron.

[ericab]

thanks largon;

hopefully i will have better luck with my next card.

since my last post ive RMA'ed it. since i unsolder ed everything and the cap fell off, my temperatures at idle were ridiculous. (around the 75C mark ), and on load you can only imagine. sigh.

[largon]

A missing cap could not possibly cause such a temp anomaly. No doubt about it.

[funkflix]

Anyone here with a vmodded GTS or better two on a 790i board? I have some strange things going on here..

I'm 100% sure that both GTS are set to 1.333V idle before i put them on to the XFX board(tested on P35 and AMD 790FX), but now i measure just 1.118V in idle on both cards.. When i disable the mods then i measure just 0.996V in idle, thats less then the default specification for the GTS.

Hope someone can help me here!

Edit: Problem was a empty battery on my one DMM..