Volt mod 7800gtx 512mb?

[granulf]

Hi. I ran across this guide for volt modding the 7800gtx 512mb: http://www.vr-zone.com/?i=2943
I was primarily thinking of giving the core more volts(1.65V?), but I need to have some first hand experience and maybe some pics of the work before I proceed doing it . I'm sure lots of people here have done the mod, but I couldn't find anyone(unlike the 7900gts )

[granulf]

Anyone?

[K404]

What ya need? pics, or evidence that it works? I got my volt-modded GTX 512 here, anythin ya need, gimme a shout

K

[granulf]

What ya need? pics, or evidence that it works? I got my volt-modded GTX 512 here, anythin ya need, gimme a shout

K

Pics would be great . And a short "guide" would also be appreciated. How much longer can you overclock? And what cooling you got? I reckon my mcw60 should be plenty? Do you run with volt mod 24/7? How long have you been running it? And was it hard? I've done a few modifications on hardware previous, like volt modding asrock 939 dual sata2 and chipped a few xboxs...

Thanks for reply

[K404]

well...it all comes down to cooling. I`m back on the stock cooler at the mo, so my volt-mod is disabled, when i`m on water, its fine 24/7. If you pick pots with a high value, they can be tuned to give a lower voltage increase when not benching, so the chance of any damage can be tiny.

If you`re handy with a soldering iron, and the guide is good, you should be fine. I`ll get some pics up for ya, but really, Shaminos guide is about as good as it gets

I`ll be honest, it was Andreyang that did these mods, but i`ve modded GPUs and mobos before, its more of the same, exept Andres work is neater than mine LOL

[K404]

Sorry..the 2nd pic is a bit crap. The wires curving down in pic 1 end in pic 2.

[granulf]

Well, my first thought was that it looks a bit more complicated than I first thought . And I also found out that I don't have a variable resistor either. Doh! I only got loads of those not variable ones...

So on water, how much further could you overclock? Before and after?

[K404]

Stock clocks 580/1745.. while keeping the voltages sensible (1.55/2.3) 670/1880 ishhh I`ve still to really let rip with the card, I wanna aim for 700 on the core before I REALLY cool the card

a 50K pot for the core and a 500 ohm pot for the RAM will allow you to vary the voltages between not-much-over-stock and plenty-of-juice. Dont worry, despite how it looks, you`re connected a variable res between 2 points for each voltage, and the molex and its wires are just to make it easier to read the voltages with a DMM. I`d say start with the molex read-point part.. a gentle break-in for the soldering and for the mod, and is unlikely to kill anything

K

[granulf]

Stock clocks 580/1745.. while keeping the voltages sensible (1.55/2.3) 670/1880 ishhh I`ve still to really let rip with the card, I wanna aim for 700 on the core before I REALLY cool the card

a 50K pot for the core and a 500 ohm pot for the RAM will allow you to vary the voltages between not-much-over-stock and plenty-of-juice. Dont worry, despite how it looks, you`re connected a variable res between 2 points for each voltage, and the molex and its wires are just to make it easier to read the voltages with a DMM. I`d say start with the molex read-point part.. a gentle break-in for th soldering and for the mo, and is unlikely to kill anything

K

Well that sure is a nice increase . I can just barely reach 610/1800 on stock volts, so I might be able to go even further than you with a volt mod?

But now I need to find a variable resistor :p

ohh, and btw, I don't have a multimeter or what ever it's called to measure volts, but I think a friend of mine got one...

[K404]

Please dont try this without one I have my DMM hooked up for the bootup, the second I see something I dont like, off goes the computer

[granulf]

Please dont try this without one I have my DMM hooked up for the bootup, the second I see something I dont like, off goes the computer

Got a link for the dmm?

[K404]

cant think of any big makers of multimeters..your local hardware store should have them

EDIT: err...yes I can! Fluke are the daddies But expensive. Ebay has a good selection

[granulf]

cant think of any big makers of multimeters..your local hardware store should have them

EDIT: err...yes I can! Fluke are the daddies But expensive. Ebay has a good selection

Ok, but wouldn't it be inpractical to have a multimeter connected on every boot up?

[K404]

Not massivley, but once ya know the mod is good, you`d only need it connected when you`re changing voltages

[granulf]

Do you have a link for the variable resistors mate? I'll be gone on a vacation for a few weeks, but I should have lots of spare time after that! I mean, I can't let a stock 7900gtx beat me, so I'll have to match at least a reasonable oced 7900gtx to be pleased (680/1900 perhaps? Should beat a 7900gtx nicely!)

[K404]

any hardware store? Radioshack in the US, Maplin in the UK? Where are ya based?



K

[granulf]

Norway!

Anyhow, could you or someone else find a suitable one here?
http://www.elfa.se/en/

And also, I can run this mod 24/7? Because I'm not THAT interested in benching, but my card is struggling a bit with fear, condemned, bf2 and so on at 1680x1050. I would imagine an extra 50-60mhz on the core would help me . But 1.55V should be fine on water? It's a 110nm core, so it should be able to deal with the volts, right?

This one would be fine, right? 64-349-22 search for it
plus the 100k on the same page

[granulf]

As for the Vmod for the core, where can I find ground? Any easy to solder suitable spots?

[kiwi]

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

[granulf]

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

Thanks, but that picture looks different oppose to the other guide?







But the second one is actually pointing at the same point or what??


And one more thing, there isn't a problem running with so long cables?

[granulf]

And one more thing: When measuring Vcore og mem volts, I take the red point at the specific vcore point and the black ono to ground, right? What ground should I use?

[K404]

Any ground..ground is ground all the components in a computer case should be at the same reference level

You said you`ve modded stuff before...you should know all this?

[granulf]

Any ground..ground is ground all the components in a computer case should be at the same reference level

You said you`ve modded stuff before...you should know all this?

Lol, I've barely tried a multimeter

I could probably just stick it into a molex for ground as well, if any ground is fine?

Me modded stuff before? Sure, soldered it, plugged it in and worked . Don't want to break this expensive graphic card though(or maybe I could get my money refunded, something like 970$ )

[K404]

yup, a molex ground is fine

[granulf]

Ok, I'll order a multimeter and two variable resistors in a few weeks then, hopefully I'll manage the soldering. Is it reccomended using "soldering paste"? Or will I be just fine without? Some mobos have been really hard soldering on without...