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Im currently feeding maximum voltage available in AI7 mobo (3.2V) for my KHX PC3000 sticks, which naturally isnt enough, for those Winbond BH-6 chips. I need atleast 3.45V to run these sticks at 260MHz 2-2-2-5 speeds.
So does anybody know, how to vdimm mod this mobo?
Thanks :)
Bump^^
Does anybody know where to measure current VDD voltage?
im also interested in this. i looking to get this board for a 2nd box. and a vdimm over 3.2v would be a must. somebody needs to find out what regualtor its using so they can determine how to do the mod. hopefully soon somebody will figure it out :)
Solved it by my self :D
For higher memvolts, you need PSU with "trimmed" 3.3V line to get more voltage for memory.
Solder 10ohm vr, on the other end (closer to NB) of R153 resistor, and the other wire from vr to ground.
Do NOT unsolder R153, like R50 resistor in IC7 / IS7 mobo.
When using 10ohm vr, actual VDD is ~ -0.04V from 3.3V line.
(mine: 3.3V line = 3.43V, Vdimm = 3.38V).
You can measure current Vdimm voltage from upper (right) corner of mobo, from mosfet Q11 or Q13 lower leg.
No pics sorry :(
check these pics here maybe that will help out.
nice i'm getting Ragnorak/Mjollnr to mod an Antec TC PSU's 3.3v rail upto 3.75v for me for this purpose :)
are the vdimm measuring points the 2 black square boxes in the lower left of this pic http://www.fileshosts.com/pentium4/D...b/AI7_064.html ?
do you mean just psu's modded 3.3v rail would not work, you need to mod the board too ?
Seems abit moved well away from the IC7 design on this board.
Does Vref track well with the vdimm mod in place?
yes you need to mod the board and your psu. raising the 3.3v rail will do nothing without the board being modded. the resistor on the board wont allow you to go any higher than 3.2v.Quote:
do you mean just psu's modded 3.3v rail would not work, you need to mod the board too ?
No. You can measure vdimm from those mosfets, near atx connector. http://mbnet.fi/elixir/AI7-Vdimm.jpgQuote:
Originally posted by eva2000
are the vdimm measuring points the 2 black square boxes in the lower left of this pic http://www.fileshosts.com/pentium4/D...b/AI7_064.html ?
thanks confirmed just 3.3v rail psu mod won't work ... had 3.3v between 3.4-3.6v and vdimm still stuck at 3.2v hehQuote:
Originally posted by esoteradactyl
yes you need to mod the board and your psu. raising the 3.3v rail will do nothing without the board being modded. the resistor on the board wont allow you to go any higher than 3.2v.
anyone got pics of this mod ?
Here is a pic of that mod:
http://koti.mbnet.fi/sir_hatt/miro/m...7-Vmem-Mod.jpg
Wire is actually soldered only the other end of resistor R153, not to MC245 condensator. Guy who did that mod, must have little shaky hands... :p:
thanks mate... guess i gotta learn how to soldier after Xmas :)
The Stilt
What volts can you get out of it now??
When the vr is set to 10ohms, VDDR is PSU +3.3V line, ~ - 0.04V.Quote:
Originally posted by Tedinde
The Stilt
What volts can you get out of it now??
After the mod, there is no limit for maximum voltage, if I set PSU +3.3V line to 3.6V VDDR is ~ 3.55V
thanks
So then the 10 ohm resistor is attached to the ends of those two wires?Quote:
Originally posted by The Stilt
Here is a pic of that mod:
http://koti.mbnet.fi/sir_hatt/miro/m...7-Vmem-Mod.jpg
Wire is actually soldered only the other end of resistor R153, not to MC245 condensator. Guy who did that mod, must have little shaky hands... :p:
And what does vr mean in this context: "Solder 10ohm vr"
Thanks!
Quote:
Originally posted by nleahcim
So then the 10 ohm resistor is attached to the ends of those two wires?
Yep.
And what does vr mean in this context: "Solder 10ohm vr"
vr = Variable resistor :)
Thanks!
OK one other thing - do you know how much current will be running through this potentiometer? Well - actually the wires connecting the potentiometer. Since the parts I'll be soldering to are so small - I'd like to use as fine of wire as possible.Quote:
Originally posted by The Stilt
also - does vdimm increase or decrease when resistance is increased? Thanks!
Dunno about the current, but I used wire with 1mm diameter so any wire should be able to handle the current.Quote:
Originally posted by nleahcim
OK one other thing - do you know how much current will be running through this potentiometer? Well - actually the wires connecting the potentiometer. Since the parts I'll be soldering to are so small - I'd like to use as fine of wire as possible.
also - does vdimm increase or decrease when resistance is increased? Thanks!
I found that 10 ohm resistance works best, because AI7 is capable to give 3.2V Vdimm by default. (Vdimm is ~ -0.04V from 3.3V rail, when 10ohm resistor is used). Lower resistance, causes that mobo wont boot.
So it could be made using only 10ohm fixed resistor:D Thats good to hear cos the electronics shop at my town didnt have 10 ohm VRs. Now all I need to do is find 10ohm resistor somewhere(where did I put my old psu...)
Anyone wanna fix that broken pic link so I can see how it's done?
it's better now, thanks.
Thanks for info I will mod mine.Can I use grabbers.:D
Might try it this night cos Im gettin so bored! Hope I dot fry the mobo;)
Didnt try it after all cos after looking at the resistor I realized that I need much smaler tip for my soldering iron. Well maeby tomorrow:D
Can you set the Resistor to 0???
Nope. ~10ohm is the minimum...Quote:
Originally posted by skate2snow
Can you set the Resistor to 0???
What's your higher FSB?
Mine @ 295 MHz some times completes Super PI, with VDD @ 1.65v (1.69v from monitor).
I'm using a 2.4C... this works @ 3.7 GHz with no problems, but i need an higher FSB... any idea to get higher FSB?
Does anyone have another pic of the mod?
The person that is gone to do it to me is confused .
Thanks in advance
anyone done a vdd (northbridge) voltmod?
fFletchs
For the mod is needed a 10ohm or 100ohm ???
I'm asking that cuzz this site ...u refer 10ohms they refer 100ohms, what's the correct value after all ??? :confused:
Thks in advance!
Can anyone help me And Vortan Please ?
Bump.
Anyone have a picture of this?
I think VoRtAn_MaDgE posted a link with a picture in. I think it would be safer to use a 100 ohm resistor instead of a 10 ohm resistor.
going up....
Sorry to dig up this post again, but I cant see the pictures. I want to take my AI7 out to 3.6v vdimm.
Need the pics so as not to make a mistake.
MY 3.3v line is at 3.55v, but that does nothing, the AI7 vdimm is stuck at 3.2v.
Some one post the photos back up please :)
http://www.cooling-masters.com/vmod....10&marque=ABIT
R153 to ground. 10ohm will give you 100% of 3.3v rail.
You will need 3.7v to hit 3.6v as vdimm is about .1v off of 3.3v rail. Atleast that is what I noticed.
Yeah, fishy has experience with this mod. 10ohm works great.
-CaT
ok, PS is already modded, can do 4v+ on the 3.3v rail if I need to. Right now is sitting on 3.55v.
Appears a 10 ohm resistor is a better choice rather than a VR.
Wish there was a AGP/NB mod for this board, or others?
Got a 10 ohm resistor today, only cost 10 cents. lol.
Mod worked.
Like you said, about ~0.1 lower than whatever the 3.3v rail is (rail is adjustable). Tryed upto 3.7v on the 3.3v rail, which would be 3.6v on the vdimm. Tryed all various other higher and lower voltages.
Couldn't gain anything. In fact was more unstable, and showed more memtest errors, no mather if voltage was high or low.
I have also tryed the OCZ DDR booster in the past on my board, and obtained the same results.
The fact is, my board and Mushkin 3500 LvII BH-5, likes the Vdimm without mods.
I ran a wire to R153 held down by the far right mounting bolt (in photo, so it wouldn't fall off), then to 10 ohm resistor, and then wire across to mounting bolt on the far left of the photo as ground.
Here is a picture of how I did mine (sorry for the bad photo).
http://img243.echo.cx/img243/3158/vdimmmod3ry.jpg