1. Welcome to TechPowerUp Forums, Guest! Please check out our forum guidelines for info related to our community.

Radeon HD 4850 Voltmods

Discussion in 'Articles' started by W1zzard, Jun 28, 2008.

  1. W1zzard

    W1zzard Administrator Staff Member

    Joined:
    May 14, 2004
    Messages:
    14,630 (3.94/day)
    Thanks Received:
    11,361
    Last edited: Jun 28, 2008
    klva80, xvi, brandonwh64 and 27 others say thanks.
  2. boogerlad

    Joined:
    Jun 29, 2006
    Messages:
    219 (0.07/day)
    Thanks Received:
    12
    wizzard, is the smd capacitor that you are showing on the vgpu voltage mod ground?
    Last edited: Jun 30, 2008
    yanahs says thanks.
  3. Scrizz

    Scrizz

    Joined:
    Aug 22, 2007
    Messages:
    2,834 (1.13/day)
    Thanks Received:
    378
    Location:
    Florida, US
    thx
    yanahs says thanks.
  4. newtekie1

    newtekie1 Semi-Retired Folder

    Joined:
    Nov 22, 2005
    Messages:
    19,653 (6.23/day)
    Thanks Received:
    5,830
    How are the overclocking results with these mods? Does it help the poor overclocking issues any?
    Crunching for Team TPU 50 Million points folded for TPU
  5. W1zzard

    W1zzard Administrator Staff Member

    Joined:
    May 14, 2004
    Messages:
    14,630 (3.94/day)
    Thanks Received:
    11,361
    the big yellow cap on the left side of the vgpu mod is gnd
  6. Kaleid New Member

    Joined:
    Jun 30, 2008
    Messages:
    117 (0.05/day)
    Thanks Received:
    16
    I'm thinking about doing the pencil mod (for the first time since the days of Duron)
    I'd like to have a bit more information if possible.

    1. What kind of pen to use?
    2. How much do you shade with the pen?
    2.5 As I've understood the more shade the less resistance and thus higher voltage. Correct?
    3. Do I need a Digital Multimeter to measure the VDC+resistance (I'd rather not at all)
    4. Do I need to download a new firmware to the card? If so, then where? (Ordered a Sapphire 4850)

    Thank you for your hard work :)
  7. calvary1980

    calvary1980 New Member

    Joined:
    Dec 26, 2007
    Messages:
    1,801 (0.75/day)
    Thanks Received:
    310
    Location:
    Toronto, CA
    #2 pencil and a multimeter.

    - Christine
  8. Kaleid New Member

    Joined:
    Jun 30, 2008
    Messages:
    117 (0.05/day)
    Thanks Received:
    16
    Thanks for the replies. I guess I have to chicken out then... :(
  9. scamps New Member

    Joined:
    Oct 24, 2006
    Messages:
    29 (0.01/day)
    Thanks Received:
    13
    Thank you, W1zzard!

    Is there already any software to manipulate the VGPU under Windows when I have done this Voltmod? Or is it necessary to flash the bios for each alteration?
  10. HeLLscream New Member

    Joined:
    Jul 6, 2008
    Messages:
    1 (0.00/day)
    Thanks Received:
    0
    Thank you so much.I searched a lot this.
  11. ViciousXUSMC New Member

    Joined:
    Jul 4, 2008
    Messages:
    117 (0.05/day)
    Thanks Received:
    14
    Just connect the two solder dots the pencil point is pointing at to short that out? Seems easy enough, but was wondering why only one picture actually shows a line drawn between the points? I guess it has something to do with the "paint"?

    Anyways wonderful guide!
  12. W1zzard

    W1zzard Administrator Staff Member

    Joined:
    May 14, 2004
    Messages:
    14,630 (3.94/day)
    Thanks Received:
    11,361
    the line in the picture is to clarify that you have to pencil between the points across the pcb. usually you pencil on a component like a resistor
  13. ViciousXUSMC New Member

    Joined:
    Jul 4, 2008
    Messages:
    117 (0.05/day)
    Thanks Received:
    14
    Thats what I thought, thanks for clerifing.

    Im dead in the water right now with both my 4850's I think a bad bios flash, or corrupted drivers. O a combo of both the bios flash made the drivers go fubar.
  14. DavyGT Guest

    I know that this is an ubernoob question, but how do I measure the VGPU voltage? I'm guessing it doesn't matter where the + and - leads go, just at one any one of the points. Am I correct?
    Can someone also post some benches of their new overclocks as well?
  15. ShadowFold

    ShadowFold New Member

    Joined:
    Dec 23, 2007
    Messages:
    16,919 (7.07/day)
    Thanks Received:
    1,644
    Location:
    Omaha, NE
    What kind of pencil would I need to do a pencil mod?
  16. DavyGT Guest

    A good 2B or 4B pencil. I used my Faber Castell 2B pencil. Strangely enough, my 4B pencil doesn't decrease resistance at all, only adds to it, so always have an alternative at hand.
  17. W1zzard

    W1zzard Administrator Staff Member

    Joined:
    May 14, 2004
    Messages:
    14,630 (3.94/day)
    Thanks Received:
    11,361
    you put the red probe to the measure point and the black probe to any ground which could be case metal, molex connector black cable, pcie power plug gnd or a million other spots. the grounds are all connected with each other
  18. boogerlad

    Joined:
    Jun 29, 2006
    Messages:
    219 (0.07/day)
    Thanks Received:
    12
    another uber noob question: how much wattage for the resistor? i found various 100k ohm variable resistors, but they come in different wattages.
  19. LifeOnMars

    LifeOnMars New Member

    Joined:
    Jun 20, 2008
    Messages:
    2,566 (1.16/day)
    Thanks Received:
    396
    Location:
    Kettering,Northants. UK
    Any ideas on how long the pencil would stay on there for once modded? Never done this before and don't want to have to keep applying every two weeks, thanks.
  20. LifeOnMars

    LifeOnMars New Member

    Joined:
    Jun 20, 2008
    Messages:
    2,566 (1.16/day)
    Thanks Received:
    396
    Location:
    Kettering,Northants. UK
    so for that first pencil mod are we putting it on top of that one already filled or the empty one next to it?
  21. LifeOnMars

    LifeOnMars New Member

    Joined:
    Jun 20, 2008
    Messages:
    2,566 (1.16/day)
    Thanks Received:
    396
    Location:
    Kettering,Northants. UK
    no worries, all sorted. Now at 790/1180 stable :) £117 quid well spent
  22. yanahs New Member

    Joined:
    Jul 23, 2008
    Messages:
    21 (0.01/day)
    Thanks Received:
    0
    hi guys.. quick question if I use the first pencil mod.. which only alows 1.4 volts (no more).. does that mean i can actually just pencil as much as I want without worrying overvoltage? (no need a dmm)?
  23. tomcug New Member

    Joined:
    Jan 5, 2008
    Messages:
    96 (0.04/day)
    Thanks Received:
    16
    Yes, I think you can't kill your card with the first pencil mod, but everything depends on your cooling. If you have a good aftermarket cooler, you don't have to worry about anything. But if I were you, I wouldn't do this without DMM.
    yanahs says thanks.
  24. yanahs New Member

    Joined:
    Jul 23, 2008
    Messages:
    21 (0.01/day)
    Thanks Received:
    0
    I got an accelero on it and i get 38 ide 45 load.. what do you think sufficient?
  25. tomcug New Member

    Joined:
    Jan 5, 2008
    Messages:
    96 (0.04/day)
    Thanks Received:
    16
    If you have Accelero S1 on it, then you can try that pencil mod. But remember to check temperatures all the time, especially #2.
    yanahs says thanks.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guest)

Share This Page