7800GTX overclocks with Volt Mods??

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Originally Posted by eclypse

Download nvflashv513.exe. Now unzip the contents to a blank formatted floppy disk and also load your original bios (just encase theres something wrong with the new one) and the new edited copy onto it.

Make a bootable floppy for you can get into pure DOS.. If you dont know how just take a blank floppy disk and insert it into the floppy drive. Open up windows explorer and right click on the A drive and select make a bootable disk.

Now boot the computer with the bootable disk installed in the floppy drive. There will be some options that come up on the screen asking you if you want to boot into windows ect..ect.. Choose the one that says command prompt.

Now put in the other floppy disk with the nvflash and your original and edited bios.. Type nvflash.exe -5 -6 "name of the bios file .rom" and hit enter.

It will search for the card and when it finds one it will ask you if you want to flash this card and hit "y" i think or enter for yes.. Reboot without the floppy disk and your all good to go. If theres any probs do the flash again but this time with your original bios.

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thanks for the help, much appreciated

do these cards have ovp? whenever i give the core more than 1.6v it locks up? is there a way round this?

i think the mod actually targets the part of the card that senses voltage by making it think theres less voltage than tehre really is.

I just think GTX's dont like too much voltage

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Originally Posted by cheap

do these cards have ovp? whenever i give the core more than 1.6v it locks up? is there a way round this?

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Are you setting that 1.60 Vcore while idling at the Windows desktop in 2D mode??? If you are that would put the Vcore at about 1.87 when that card goes into low or high power 3D modes with a stock bios.

Viper

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Originally Posted by ViperJohn

Are you setting that 1.60 Vcore while idling at the Windows desktop in 2D mode??? If you are that would put the Vcore at about 1.87 when that card goes into low or high power 3D modes with a stock bios.

Viper

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no. im running 3d mark 2003 and checking the voltage while its running. it measures 1.6v. if i adjust it any further i get a lockup.
At what point should i increase the voltage? while running a 3d aplication or at idle in windows?

I wouldn't go beyond 1.7v

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Originally Posted by Mysterfix

I wouldn't go beyond 1.7v

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what about your score in 3dmark05?

Is it possible to do the mod using a pencil on c569 for vddr and c525 for vgpu?

I've seen the question about pencil mod several times without any answer, so I guess it is not possible or nobody figured that out yet

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Originally Posted by G-Man

Is it possible to do the mod using a pencil on c569 for vddr and c525 for vgpu?

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It should be possible to pencil mod the Vdd on the 7800GTX, but I don't think that you would gain much from pencil modding the Vgpu, due to the low value of the feedback resistors in the Vgpu regulator.
I don't like pencil mods myself (because they are much too risky IMO), so I'm a bit reluctant to find pencil mods for the card, but someone really needs them I might be persuaded to look into them ;).

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Originally Posted by kiwi

I've seen the question about pencil mod several times without any answer, so I guess it is not possible or nobody figured that out yet

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Pencil modding on Vcore would not work at all as the resistances involved are to low.

They would work on the Vmem mod, assuming you could even get the lead to stick, but with the resistances involved there you may way overshoot the mark.

Pencil modding is at best a hack and a half.

Viper

ViperJohn a bit of OT
I was going to vmod my GTX over the holidays and I have a nice Xeon HSF to put on it. However, where the heck do you get the screws thin enough to fit through the PCB holes?! I looked everywhere.

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Originally Posted by IvanAndreevich

ViperJohn a bit of OT
I was going to vmod my GTX over the holidays and I have a nice Xeon HSF to put on it. However, where the heck do you get the screws thin enough to fit through the PCB holes?! I looked everywhere.

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You can use 2-56 screws. You can buy them by the 100 from Mcmaster Carr or hit your local hobby shop.

Viper

damn i'll have to buy a 7800GTX to vmod it (using "no wires" this time ;) )

i'm using 1,5V on my GTX now für 24/7, what do you think is the max vGPU i can give for 24/7?

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Originally Posted by Supertim0r

(using "no wires" this time ;) )

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Thta is the best and cleanest way.

Viper

why shouldn't you use wires to attach to the pcb and then to the trimmer. other than not liking the look of the wires is there any other reason not to use wires?

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Originally Posted by cronic

why shouldn't you use wires to attach to the pcb and then to the trimmer. other than not liking the look of the wires is there any other reason not to use wires?

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Read through the whole thread and you will see ViperJohn give his explanation for this at least twice that I can remember.

I ended up going with wires simply because I planned to change the voltages often, and inside of a case it was very hard to change voltages on cards in SLI with the recessed vGPU pot.

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Originally Posted by Weee

Read through the whole thread and you will see ViperJohn give his explanation for this at least twice that I can remember.

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Thanks - I would have typed it out again if I had not seen this lol.

Viper

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Originally Posted by Barr3l Rid3r

what about your score in 3dmark05?

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Sorry man, I just saw this, here ya go 3dmark05

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Originally Posted by Mysterfix

Sorry man, I just saw this, here ya go 3dmark05

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Your memory speed is killing you.

Viper

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Originally Posted by ViperJohn

Your memory speed is killing you.

Viper

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I know, I'm in the process of tweaking it right now. I got it up to 1390 so far and I'm running stability test as we speak. It seems that the core on this card is very strong but the memory is lacking a bit. :)

EDIT: Well after some hours of testing I'm at my max on this card for memory. The memory won't go any higher without puking all over the screen and locking up the computer. It was good for another 100 points in 3dmark05

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Originally Posted by ViperJohn

Here are the as modded Vcore pictures. The trimmer is a 200 ohm, 25 turn and gives a .050
Vcore bump at full resistance. Adjustment is extremely smooth with very high resolution.
.001 volt changes are easy to dial in.

The Vcore metering point is the clip post soldered at C792 in the 3rd picture.

Viper

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are there any pics that show a vddr mod as good as these do for the vgpu?

Viper or other?
http://jason57.iwarp.com/148gskillfx...48fx/ddddd.JPG

A freind of mine did the mod today but soldered to the solder pad under the one in your guide. What is this? Is this part of the circuit a ground or something away from it all?

Thanks
Please respone ASAP
Kazoo

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Originally Posted by Kazoo

Viper or other?
http://jason57.iwarp.com/148gskillfx...48fx/ddddd.JPG

A freind of mine did the mod today but soldered to the solder pad under the one in your guide. What is this? Is this part of the circuit a ground or something away from it all?

Thanks
Please respone ASAP
Kazoo

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That pad and the one above it are traced together so it will still work. The GenRad test pad normally used (and above where your friend made his connection) was chosen because it was larger target for people to land on.

Viper