ok, i mean between this chip pin 5 what give me 1,26v and ground for gpu mod ?Quote:
Originally Posted by persivore
amm, 100 kohm is max resistance ? it give me max v's and if i lower resistance, v's will drop, ok ?
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ok, i mean between this chip pin 5 what give me 1,26v and ground for gpu mod ?Quote:
Originally Posted by persivore
amm, 100 kohm is max resistance ? it give me max v's and if i lower resistance, v's will drop, ok ?
Pin 5 on the chip is feedback - putting a 100k variable resistor between this pin and ground will trick the regulator into giving out more voltage. To increase the voltage that the regulator gives out, you decrease the resistance of the variable resistor. Pin 5 was the pin that you measured the resistance to be ~5.8k
ok, 100kohm resistor increase volts or is it 1:1
is there possible somehow calculate how much 90kohm :rolleyes: will give ?
yes, but it can be slightly complicated, and doesn't always give very accurate results, and you will need to know the resistance between pin 5 and the voltage that you are modding's read point. You can use Vout=1+(Rfb/Rg)*Vref, where Rfb is the resistance between pin 5 and the read point,Rg is the resistance between pin 5 and ground, and Vref is the internal reference voltage for the regulator (I told you that it was slightly complicated ;))Quote:
Originally Posted by Melx
I think a 90k resistor will give about 0.1v over stock, but I can't be sure.
ok, you think that 100kohm resistor wont blow my card up :p:
mb i connect pin5 and ground with plain 100kohm resistor and then read v between pin8 and ground, then i see something for starting :rolleyes:
I'm 99% sure that a 100k resistor won't kill the card. You can use pin 8 to check the voltages, but they might be about 0.02v under the true voltage reading.Quote:
Originally Posted by Melx
deem, i think i read wrong pins resistance, you marked those pins other side, i did reading from side where i read volts :nono:
you think yellow pins on this picture ?
I needed the resistance from the pins that you've marked in yellow. Can you re-check the values on the yellow pins?
Ok, Thanks for the readings.
Vgpu (1.26v) mod - connect a 20k variable resistor between pin 5 on the Vgpu regulator and ground.
Vdd (2.79v) mod - connect a 50k variable resistor between pin 5 on the Vdd regulator and ground.
Vddq (2.62v) mod - connect a 20k variable resistor between pin 5 on the Vddq regulator and ground.
ok, and volts i read between pin8 and ground like allways :)
what is vdd and vddq, some sort of memory vmods ?
yea, read the volts at pin 8.
Vdd is the main Vmem mod, and the Vddq mod is to increase the I/O voltage that the mem chips use (although it doesn't usually have much effect and can be sometimes be dangerous for the card)
hmm, seems that it works, but my multimeter is going crazy when i read volts after vmod, i think its prob of this cheap :banana::banana::banana::banana: crapy multimeter :stick:
i soldered pin5 and ground with 19kohm resistor and got +10MHz for gpu :rolleyes:
A 19k resistor will probably give an overvolt of about 0.06v, so a 10mhz gain is quite good for that IMO.Quote:
Originally Posted by Melx
ok, hope this pic will help if somebody need vmod in future ;)
X600 XT Vmods
persivore maybe you can help me you vmod god ;) I have a MSI version of the x600xt I dont have the same IC's Melx has so I dont know where to start, also if a pencil mod is doable that would be handy here are a couple pics of the card.
http://img225.echo.cx/img225/5460/front3rm.th.jpghttp://img225.echo.cx/img225/7041/back6wa.th.jpg
Can you tell me what is written on the 2 chips I have circled. The chip on the left will probably be an ISL6522CB for the Vdd/Vddq.
Edit: forgot to attatch the pic.
ISL6522CB is top left and the top right is T8964 MS141
Can you check the voltage at the point I have marked. I'm still looking for the datasheet for the other chip.
Sry persivore I sent the card back to newegg they posted the wrong specs for the card and am currently trying to pick out another one, the other chip you cant find it was the number on the sticker probuably why you cant find it and didnt want to rip it off and make it look too obvious when going to RMA it.
Hi persivore my card is very much like the first but the one chip is not there. I labeled the chips you might need but found you may not be able to read it. :( If you want I'll relabel it. :)
http://img93.echo.cx/img93/1150/picture2930qf.th.jpg
It looks like one regulator is being used for Vgpu, and the other is probably used for both Vdd and Vddq. Can you check the voltages at the points I have marked here please.
Well I tested the points you showed and got 0V on both chips. I tested the pins on the exact opposite side and had some readings. I marked the drawing w/ the pins I checked and their readings. Thanks. :)
http://img295.echo.cx/img295/729/pic...ings2rw.th.jpg
It looks like the Vgpu regulator is the same as the first card, so the same mod should work for that (connect a 20k variable resistor between pin 5 on the Vgpu regulator and ground).
The other regulator will probably be powering Vdd and Vddq (unless there is another regulator on the front of the card). The Vdd mod on this card should be the same as the one on the first card, but to check, can you check the resistance between the point I have marked here and ground.
I believe there is another reg. on the front. When I get home I'll check the res. as you showed. Now on the cards how are the pins numbered does it go as follows?
7,6,5,4,3,2,1
14,13,12,11,10
Also do you know which pin on the reg. would be the ground leg? I think it looks neater modded right from one pin on the reg. to another instead of jumping to ground in the front of the card. If you have any links to pages on chips or where I might research a bit I would appreciate it. Thanks so much for your help so far. :toast: