X800 Pro / X800 XT Voltmods?

[Mickey Padge]

I did both the vmem and vddq mods, both with a 50k VR. Pin 5 and pin 7 ( ground ) were used on both mods and it did work
The read points work as stated too

The strange thing is my ram would not run stable over 470 even with the mods

I did notice that AGP voltage ( 1.5-1.8 on the NF7-S Rev2 ) had a direct effect on artifacting. Higher voltage gave less artifacts as you would expect

Just for the hell of it I dropped my AGP down to 4x from 8x and damn if all my problems went away

I have my ram at 570 now with no problems at all and no volt mods attached !! I have not tested this VGA card on another motherboard so I have no idea if its the board or the VGA card causing the problem.

Out of interest I assume the drop to 4x AGP will give a minimal performance drop if any ? The increased ram speed will easily offset any performance drop I would imagine.

Just thought I would let you guys know my results I don't even think I will re-attach my mods now, as 570 is more than enough for me

Cheers

[Bloodymaster]

@all

By what Voltage from Vcore do i need the 500k VR resistor ???


Do i need the 500k VR for stbilisation or what ???

can i leave the 500k VR out , or is this not good vor my card ???

Or can i used an other VR as 500k ??


Bye Bloody

[Blaster]

Originally posted by Bloodymaster
@all

By what Voltage from Vcore do i need the 500k VR resistor ???


Do i need the 500k VR for stbilisation or what ???

can i leave the 500k VR out , or is this not good vor my card ???

Or can i used an other VR as 500k ??


Bye Bloody

the 1596 mod allows u to achieve greater core speed

in my opinion u should only do it if u phase change ur card

from my experience it allowed me a 20Mhz increase in core speed... but im still experimenting

[Bloodymaster]

@ Blaster

ok thanks for your opinion

so i leave him out why at this moment i cooled with water , and later when my Mach 2 @R507 ist coming i do it for better core Speed !!


How high did you get your Card with Stock , with Water and then with comp ???

[Blaster]

Originally posted by Bloodymaster
@ Blaster

How high did you get your Card with Stock , with Water and then with comp ???

Stock max was 560/610

prommy cooled no vmods max was 620/650

prommy and VGPu max was 685/650

prommy, VGPu and 1596 max is atm 710/650

... never tried water, prefer beer

... still have to do the vmem mods

later

[GomerPyle]

My readings are vddq 2.11 and vmem 2.11. Can vmem not go any higher than vddq?
Hve moved the resistor for the vmem mod down from 20k to 8k but no change in the volts.

[Bloodymaster]

@blaster

i have got a big problem , i set VGPU Voltage to 1,6 V for testing out the max core speed!
during the test it froze because VGPU went down to 1,4V,but i don't know why ???
Have you got any ideas why this voltage is so unstable?
But I don't change the VR it is set to 1,6 V and not for 1,4V!!But after rebooting VGPU is at at 1,4V
Can anybody help me ?Any ideas?

Bye Bloody

[Blaster]

Bloody:

take it slowly man, if ur still stock cooling u have to try to overclock it from a step at a time, what clocks were u trying with the gpu at 1,6 volts?

Gomer:

I still havent tried the vmem mods bro, gonna do it tonight prolly

[VoRtAn_MaDgE]

Originally posted by Bloodymaster
@blaster

i have got a big problem , i set VGPU Voltage to 1,6 V for testing out the max core speed!
during the test it froze because VGPU went down to 1,4V,but i don't know why ???
Have you got any ideas why this voltage is so unstable?
But I don't change the VR it is set to 1,6 V and not for 1,4V!!But after rebooting VGPU is at at 1,4V
Can anybody help me ?Any ideas?

Bye Bloody

Bloodymaster,

The reason your vga is doing that is because Vcore
regulator is initiating a Vcore Over Current shutdown of the Vcore power supply.

Or u get a better cooling for the vga or u can make the ovp mod...better do both

btw nice score on 2k3 blaster...always nice to see ppl from our country on the top

[CodeRed]

Originally posted by VoRtAn_MaDgE
Bloodymaster,

The reason your vga is doing that is because Vcore
regulator is initiating a Vcore Over Current shutdown of the Vcore power supply.

Or u get a better cooling for the vga or u can make the ovp mod...better do both

btw nice score on 2k3 blaster...always nice to see ppl from our country on the top

You just solved my problem

I was under the impression that the overcurrent protection forced the card into reset, but now you are saying that it initiates current limiting and hence the Vgpu starts to drop. When I set the Vgpu to 1.80V it drops to 1.68V under load and is really limiting my o/c.

Time to get the soldering iron back out

[cowpuppy]

Are you guy's sure the R1597 is right? here is how the 9800xt vgpu mod was done, using the R1592/R1597 resistors and to make it easier I only used the R1592 to ground on my 9800xt.

[cowpuppy]

The R1592 resistor to ground mod for the 9800xt, this was drawn up by charlie.

[CarNabY]

Stock max was 560/610

prommy cooled no vmods max was 620/650

prommy and VGPu max was 685/650

prommy, VGPu and 1596 max is atm 710/650

... never tried water, prefer beer

... still have to do the vmem mods

later

For igpu you have used 500k VR resistor? Fixed to 500k? I have seen others mod with 250k under 1596!! These Igpu mod it increases the voltage or it stabilizes the voltage?

Thx

[CarNabY]

Up

[VoRtAn_MaDgE]

For igpu you have used 500k VR resistor? Fixed to 500k? I have seen others mod with 250k under 1596!! These Igpu mod it increases the voltage or it stabilizes the voltage?

Thx

The 1596mod helps u going higher on the voltage that the gpu can handle! Regulate it to 100k, done then!

[Goldlocke]

Hi all!

I did VGPU and OCP mod as is shown here:



I thought that maybe the OCP mod would reduce this damn drop in VGPU under load from 1.83V to 1.72V. No?
Or is my OCP mod just not working?

btw, pics are made by W1zzard.

[CaTalyst.X]

The vmem mod is killing ocs because Gddr3 just isnt voltage hungry like the ram on our 9800s and what not was

-CaT

[SIK_L_CELL]

Great thread, I am new to these forums. Mods worked like a charm. Thanks guys.

[VoRtAn_MaDgE]

Great thread, I am new to these forums. Mods worked like a charm. Thanks guys.

That's why people are here...to learn and to help...
Nice have u here

[lsevald]

Hi all!

I did VGPU and OCP mod as is shown here:


I thought that maybe the OCP mod would reduce this damn drop in VGPU under load from 1.83V to 1.72V. No?
Or is my OCP mod just not working?

btw, pics are made by W1zzard.

Same problem here. Below 1.6Vgpu I'm getting a 0.03V drop. From 1.6-1.7V the drop is around 0.06V...and closer to 0.10V above 1.8Vgpu. By tweaking the +5 and +12V rails I have been able to reduce the drop to around 0.03V at 1.6-1.7Vgpu. My board seems to like low 12V rail (12.2V is the lowest I can get), and a really high 5V rail (I have mine at 5.8V). The OVP/Igpu mod does nothing for me On the positive side my card clocks to ~700MHz on the GPU (room temp water). My current theory is that perhaps I got a GPU that pulls a bit more amps than usual. I have seen this when oc'ing low batch number AMD CPU's (runs hotter, and doesn't like Vcore as much).

I'm also measuring an additional drop of ~0.03V at high loads from the Vgpu caps to the voltage feed pins on the GPU itself:



As for the 0.03-0.06-0.10V drop, I think one of the current sharing channels is dropping out. I haven't been able to understand this fully, but this is what I currently got:



There's two hexfets from +5V->channel2->GND, and two and two in parallell from +12V->channel1->GND. By just considering the number of hexfets pr channel, I think 2/3 of the amps are pulled from the +12V rail and 1/3 from the +5V rail.

[SIK_L_CELL]

Quick question I used a 100k fixed for the OVP but I still get lockups around 680 and any voltage over 1.85 I get shutdowns. Thanks.

[Goldlocke]

By tweaking the +5 and +12V rails I have been able to reduce the drop to around 0.03V at 1.6-1.7Vgpu. My board seems to like low 12V rail (12.2V is the lowest I can get), and a really high 5V rail (I have mine at 5.8V).

thx for your input Isevald.
I thought that maybe my cheap VR could have something to do with that. But now I see you use a cermet type VR and also have this "VGPU droop" prob.
I will try changing the PSU rails and the VR to a cermet one soon...

[VoRtAn_MaDgE]

Quick question I used a 100k fixed for the OVP but I still get lockups around 680 and any voltage over 1.85 I get shutdowns. Thanks.

Cooling?

[SIK_L_CELL]

Cooling?

Ya think? I have never seen the temps go over 38c. Hmmm....

[Goldlocke]

Hehe. Thanks to Isevalds suggestion I upped the 5V rail on my Powerstream to 5.50V. The VGPU now stays at 1.80V under load.
(Upping 12V didn't help, instead made the drop worse. So, let the 12V rail low)
thx!