Radeon 9800/9800 Pro Voltmods

[W1zzard]

VGPU
SC1175 - 10k pot between pin 18 (-IN1) and pin 20 (GND)
Default: 1.6v - 1.7v
Suggested maximum:
- Air-cooled: 1.8v
- Water-cooled: 1.90v
- Extreme-cooled: 2.00v

VDD
ISL6522 - 20k pot between pin 5 (FB) and pin 7 (GND)
Default: 2.9v
Suggested maximum:
- Without ramsinks: 3.2v
- With ramsinks: 3.6v

VREF
ISL6522 - 50k pot between pin 5 (FB) and pin 7 (GND)
Default: 1.45v
Set this to 1/2 your VDDQ. More than 1.5v VREF will probably kill your card.

VDDQ
ISL6522 - 50k pot between pin 5 (FB) and pin 7 (GND) measurement point is c136 on other side.
Default: 2.7v
Suggested maximum: 2.95v

Use the middle and either the left or the right pin on the pot. There is no polarity you have to watch. I strongly suggest removing the unused pin so you can't accidentially put the potentiometer there flipped and kill your card with too high voltage.

Start with the pot set to the highest resistance (turned all the way from the outer pin you are using) and slowly work your way down while measuring voltage- you can safely change resistance while your system is running.

To measure voltages attach the negative (black) probe to your case or another grounded part and carefully put the positive (red) probe on the measurement point. Be careful not to create a short with another of the 'posts' near the measurement point.
A better way is to attach an SMD grabber.

[Ruppy]

Hi guys.

Please give me some advice.

I have a Expertvision 128mb/256bit 9800SE. I hardmodded to 9800pro. After the modification the 3Dmark2001 is 19650.
On the card I have Hynix 2.5ns ram.

I cant run over the ram frequency above 330MHz. I dont understand why? The Hynix 2.5 ram must run faster. Maybe the mem volt is to low.
I nead some info abouth the pencil trick to rise the ram voltage, or any sollution.
The pcb of the vga card more like xt pcb.

So I wanna voltmod just missin some info.
<img src=http://forums.techpowerup.com/attachment.php?attachmentid=140&stc=1>
<img src=http://forums.techpowerup.com/attachment.php?attachmentid=141&stc=1>

Other problem is the bios flashing. I always receive a (rom locked fault message)

[Ruppy]

Does anyone identify this pcb?

A little bit similar with xt.

I hunting for a "pencil trick" for this pcb.


Frank

[Urlyin]

Rubby ... can you get a closer pic of the area around the chips ISL6522 like in the XT800 Vmod here is the layout the same?

[Ruppy]

Hi. Urlyin

I cant fined any 6522 , even a lot part missing from the pcb.
On the front side I fined 3 pc of ic:NCP5424,CO257,NCT66
On the back side I fined 3 pc of ic:1575,P42AD,and on 8 legged what I cant read....maybe the bios?.

Maybe the 1575 is for the vmem?

<img src=http://forums.techpowerup.com/attachment.php?attachmentid=146&stc=1>
<img src=http://forums.techpowerup.com/attachment.php?attachmentid=147&stc=1>

The layout closer to the 9800XT. Just on the 9800xt pcb a lot of part on it. From my pcb a little bit empty only 3 pc of IC on each side.

This card from Xpertvision. I checked the www.expertvision.com.tw They produced only 9800se and 9800xt. Both on a same pcb.(with R360,2.5ns Hynix....)

And the other problem is the bios flashing. Bios is locked. The flashrom cant access. (with "flashrom -f -p 0 bios.bin")

Urlyin.

[Urlyin]

Ruppy... sorry I haven't had time to look up the ic list. From the picture only the L shaped mem is close to a X800. I've seen a 9550xt that looked close ... most of the vmods at least have the SC1175 and ISL6522. Try to get back to it as soon as I can ... maybe if you shoot a PM to W1zzard he can point you in the right direction ...

[Ruppy]

Thanx your trying to help me Urlyn

Ruppy

[Urlyin]

Ruppy ... the NCP5424 is the controller for the GVPU . You can check the ohms on pins 3 & 7, see if there is a resistor in line with pin 7 that has the same reading ... Sorry Rup that should have said 7 not 3 ...

[Ruppy]

Thanx Urlyin.

I will check it out. 0.1V rise is ok?


Do you have idea for VMEM? The 2.5ns Hynix is can be interesting.


Ruppy

Hi ruppy.
dose your ram read
HY5DU283222AF-xx <-(in your case 2.5)
i have the same ram. but the 2.2ns ver. and got the data sheet from Hynix. after i found it wouldn't reach what it was meant to. 450 (900ddr) for the 2.2ns and 400 (800ddr) for your 2.5ns
and found that the 2.8ns and down needed 2.8v VDD and 2.8v VDDQ. +/- 5% so a max of 2.94v
the card by default has 2.9v VDD and 2.7v VDDQ <-- theres the problem. uping that too 2.8v should fix the problem. i haven't done it yet but i intend to.

your vpu reads 360 yes? not 350.
in that case u also have a xt vpu. (just means a slightly optermised shader and something els i think)
so if your flash is failing u might want to try the 9800pro > 9800xt mod (128meg ver) as yes it looks like
the pcb is also the xt ver.

V nice buy btw. a 9800se which might beable to be modded to a xt! (128meg ver)

[vg]

Ruppy, I have the same card.
To flash bios use flashrom.exe with -sst switch. BIOS is SST25VF512.

Can you help me with voltmod?

Thanks

[Nobru_rv]

One question:

Do i need VREF and VDDQ mods or can i do only VDD and VGPU if i want?

[Nobru_rv]

Originally Posted by Nobru_rv

One question:

Do i need VREF and VDDQ mods or can i do only VDD and VGPU if i want?

ANYBODY?? ARe VREF and VDDQ a MUST MOD or no?

[Urlyin]

Originally Posted by Ruppy

Thanx Urlyin.

I will check it out. 0.1V rise is ok?


Do you have idea for VMEM? The 2.5ns Hynix is can be interesting.


Ruppy

Ruppy ... read my last post again, It should have been pin 7 ... try .05v increments ... looks like W1zzard has 1.8 for air cooling ...

[Urlyin]

Originally Posted by Nobru_rv

ANYBODY?? ARe VREF and VDDQ a MUST MOD or no?

Nobru ... if your card is the same as in the pics then sure you can do the VREF and VDDQ for memory ...

[Nobru_rv]

Originally Posted by Urlyin

Nobru ... if your card is the same as in the pics then sure you can do the VREF and VDDQ for memory ...

I have a 9700pro PCB as i see but i have small problems.
With 10K pot i get only 1.8V ,and memory,when i rise voltage i get less OC.How come?

[Urlyin]

Originally Posted by Nobru_rv

I have a 9700pro PCB as i see but i have small problems.
With 10K pot i get only 1.8V ,and memory,when i rise voltage i get less OC.How come?

What was the voltage before you started?

[Nobru_rv]

Originally Posted by Urlyin

What was the voltage before you started?

1.6
Do i need maybe 20k pot (actually i dont have 20,i have 22 and 25)?

[Urlyin]

Originally Posted by Nobru_rv

1.6
Do i need maybe 20k pot (actually i dont have 20,i have 22 and 25)?

Set it to 10k first then take it slow....

hi guys.

just interested to know.
(i was just checking what me voltages read)
its a 9800pro with hynx 2.2ns 350 core and 9700 pcb (only had it for a month or 2)

VGPU: 1.72v-1.73v
VDD: 2.8v
VREF: 1.43v (what acturly is VREF ? and whats it afect?)
VDDQ: -- (haven't yet found c136 i'll turn me comp off in a sec and pull the card out to look for it)
but ya. ok i'll up me VGPU to 1.8 as for VDD ya got the default as 2.9 is it fine mine being 2.8 ? is this only for the ram btw? if so. me ram says it needs 2.8v VDD +/- 5% so with +5% that makes it 2.94 which it would seam is its max recomened voltage. i might leave it @ 2.8 if its only for ram)
VREF what acturly is that? and whats it power? e.g. ram ? gpu ? something els ?
VDDQ when i find it ya default says 2.7 and i need it @ 2.8 (i persume thats why my ram won't reach its 2.2ns speed of (900mhz ddr) atm well i've droped it to 724mhz ddr as i was seeing graphic jitters after a little wile @ 750 or so mhz. but ya any thing above that and it die's up the ass. is that just coz of lack of VDDQ or would / could there be any thing els the problem. ?
and well the main thing i'm asking is. so if i want to try get more out of my ram. do i only need to up VDDQ to its 2.8v like it needs ?

thx.

ya just checked.
me VDDQ's 2.7v's
next time i'm @ dicksmiths i'll pickup some trim pots. and give it a try.

Hi, Guys, new to this forum,but not voltmods.
As for your Vref inquiry : Vref is the reference voltage of the gpu (The voltage the gpu sees as a "1", anything below that is considered a "0") (correct me if i'm wrong, but that is the standard definition of VREF in a digital circuit; should apply to vid cards too)
I have a Sapphire 9800 with Hynix mem 2.8 nS.
I bought the card off ebay for $31 (US). Guy tried modding it for a mac and messed it up.
I also flashed it with a powercolor VBIOS
When I did the voltmods, I decided to use my own method. I have a set of 4 DIP switches that allows me to turn each mod on or off individually.(while running, too) I dont have a digital camera so no pics; sry.

My voltages
VGPU: 1.85v
VDD : 2.7V
VDDQ:2.6v
VREF: 1.42v

Clocks : 435/375*2 (stock cooling with vantec tornado zip-stripped to the card)
3dmark 03 6650+ (saw 6700 once) @ 1024x768 @ 430/370 video and CPU@3.8

"The last three voltages are stock" you might point out. I found no benefit to either raising or lowering VDD, VDDQ, VREF. I only use the VGPU mod.

Here are a couple pieces of info for y'all
VDD is the main voltage of the DDR memory (3.2v MAX with ramsinks)
VDDQ is the voltage for the memory input/output buffers (also 3.2v MAX with ramsinks)
Never go over 1.50v Vref, you'll cook your gpu

Max GPU voltages
Stock cooling 1.7v max
Air cooling 1.8v max
water cooling 1.9v max
Phase change/peltier /w waterblock 2.0v

When you raise the GPU voltage, it allows the GPU to write to the memory better, but hinders read operations (relaxed read-ready timings help) but you will lose a few mem clocks

When using 2.2nS ram on a 9800 non xT PCB (R350) the speed is limited (usually 380*2) by the tracings on the PCB itself, when you up the voltage you actually can lose some overclocking potential (a few MHz)
Thats why ati changed the reference board for R360 and XT

How do I know all this? Simple, I hold a degree in computer and electronics engineering technology.

If you have any questions you can e-mail me @ gregbrown8257475@hotmail.com
I don't mind making new e-friends.

My main rig:
ABIT AS8 uGuru MB w on the fly overclocking
LGA775 Prescott 2.8Ghz @ 3.8 air cooled
512 MB (Grrr) Kingston (yuk) ddr 400 (soon to be corsair dual channel 1GB)
Modded 9800
Sata HDD
Xconnect 500w P/S

Hope this was helpful.

Hellraiser1981 that was most! useful!

thank you X10

and ark ok. i guess i'll leave me ram voltages alone then or even drop or gain VDD by 0.05 perhaps?
as i carn't quite get the 380x2 any thing above 365x2 and after a wile i start it see little hmm "jitters" i guess is the word that comes to mind. when i up it to 380 or more how ever (over what the pcb can hack) its different, u see little gray squares poping up randomly around the screen.

and atm i have 2 120mm fams in a guard placed directly over the card (covering both sides) as when i have my ram speed above 330 or so the ram sinks (thermaltank copper ones) become to hot to tuch.
but with the fans they very cool. also the gpu got to 40-50'c easy but with these fans it remains 9-12'c above room temp. e.g. atm 35'c its that cool with these fans i haven't bothered replaceing the stocked cooler.

but ya. i'll up me gpu v to 1.80 or 1.85 seaning its running so cool. and see how that go's

but ya thx heeps for that info.

OOo and Hellraiser1981 very nice over clock on ya cpu there. its nice to get a free "1ghz"

atm i got a xp2000 (stock speed 1.667ghz 1.6v 266mhz bus) yes haven't upgraided in ages and i've had it running 100% stable for a wile @ 1.990ghz or so. 333bus 1.65 but any more even if i uped it 0.05 of a volt it would still be unstable. so not to long ago i uped the voltage 0.15 so 1.75 (only uped the multiplyer by 0.5 tho) and then it seamed 100% stable after some burn tests and game playing. and it was all good. but l8r on that after noon.
i opened a pdf file in firefox and wether it just crashed or soemthing i'm not sure. but. 99.9% of the cpu was going to the crashed prog so was lagging. but theres the scerry part. my cpu was emitting noise! or little screams. (simular to what my old video card did if u zoomed into a image to much. e.g. there wasn't enough voltes getting to my ram or something like that) so ya. i quickly rebooted and set it back to its normal overclocked state and voltage. just asking was that due to me mobo unable to suply enough .. amps/voltes to it ya think ?