Can someone help me find this component so I can get my fan working on this HD 7950

Collapse
X
 
  • Time
  • Show
Clear All
new posts
  • Rob
    Member
    • Oct 2005
    • 47

    #21
    Re: Can someone help me find this component so I can get my fan working on this HD 79

    I soldered the 2N3904 Surface mount transistor on and all the fan does is twitch. It never did twitch so it tells me that maybe the transistor is not allowing enough current perhaps? I did solder it twice with 2 different transistors to make sure I didn't mess up. Both same outcome.

    Comment

    • stj
      Great Sage 齊天大聖
      • Dec 2009
      • 31283
      • Albion

      #22
      Re: Can someone help me find this component so I can get my fan working on this HD 79

      meter the fan wires to check the voltage.
      and it may sound obvious, but did you actually test the fan?

      Comment

      • SteveNielsen
        Retired Tech
        • Jun 2012
        • 2327
        • USA

        #23
        Re: Can someone help me find this component so I can get my fan working on this HD 79

        See post #3

        Comment

        • budm
          Badcaps Legend
          • Feb 2010
          • 40746
          • USA

          #24
          Re: Can someone help me find this component so I can get my fan working on this HD 79

          Check the Base-Emitter voltage to see if the base drive is pulsing also.
          Never stop learning
          Basic LCD TV and Monitor troubleshooting guides.
          http://www.badcaps.net/forum/showthr...956#post305956

          Voltage Regulator (LDO) testing:
          http://www.badcaps.net/forum/showthr...999#post300999

          Inverter testing using old CFL:
          http://www.badcaps.net/forum/showthr...er+testing+cfl

          Tear down pictures : Hit the ">" Show Albums and stories" on the left side
          http://s807.photobucket.com/user/budm/library/

          TV Factory reset codes listing:
          http://www.badcaps.net/forum/showthread.php?t=24809

          Comment

          Related Topics

          Collapse

          • aaronkatrini
            Help me find the short circuit on this WORKING Nvidia GTX1650
            by aaronkatrini
            Hi all,

            Recently picked up this GTX1650 at a local flea market for a low price and wanted to use it on my secondary PC. I first tested the card and saw the fan spin for a split second and then nothing. Immediately I thought of a short circuit. Disassembled and found a shorted SMD capacitor, injected voltage into it (1V/4A) and two Mosfets got hot immediately (QN3103 & QN3107). Desoldered these Mosfets and the card turned back to life.

            Bought replacements from Aliexpress and replaced them afterwards. Tried the card but still the saw the fan spin for a split second...
            04-18-2024, 03:15 PM
          • TyMercer
            Can I flash a working BIOS from one computer to another of the same make, model, etc?
            by TyMercer
            Apologies if this is the wrong forum, but I'm not looking for a specific BIOS file, I'm trying to understand how one makes a clean BIOS file. So here's the background. I have 2 HP EliteDesk 800 g2 mini 35w pcs. One is working fine; the other doesn't have display out or working USB's nor does it have any flashing error lights. The CPU does get worm enough to cause the fan to spin up, so I think it's posting, but I just don't know. I had it working at one point but trouble started when I tried to put in a drive caddy that had a cooling fan on it. I thought it would be compatible but wasn't...
            11-13-2025, 09:39 PM
          • Vesko356
            [Guide] How to find the right HP bios version to flash
            by Vesko356
            First of all thanks to all of our members who have posted previously all methods posted here.
            Please leave a comment if you find something new,or have anything else to add.
            -----------------------------------------------------------------------------------------

            Find by serial number,model number or series

            If you know the laptop serial or model number go to HP support https://support.hp.com/us-en/drivers/laptops .
            Enter the serial number or model number and click submit.On the next screen you will have to enter the OS
            Operating system and OS version.If...
            08-11-2023, 03:27 AM
          • Rayblaster
            HP RP7 RP7800 from 2012/2013 worst fault - has "character"
            by Rayblaster
            Hello friends, I've got a nice toy to play with - it is an HP RP7800 All-in-one POS system. I got it for free and it has one problem - it turns on very rarely, and just for a few seconds. After that it dies and doesn't come on if I don't leave it unplugged for at least 2 hours. I've repaired motherboards before, this is not my first one, but problem with these types of faults is that everything you check on the board will usually be fine. This is the case for me here.

            I dissassembled it completely, and got my hands on the motherboard. Model No. is PIQ67H/Higgins 11047-I 48.3GD02.011....
            12-30-2024, 06:28 PM
          • modtool
            HP x360 Chromebook 14A-CA, DA00GIMB6H0 REV:H, flooded, restored, slow and stuck in tablet mode
            by modtool
            Dear colleagues,
            I've entered the repair of the chromebook machines just one month ago and I've found some significant differences from the classic laptops or macbooks, so I'm searching some advices.

            The owner of this chromebook gave it to me after it has been left flooded by water for almost a week, so chances of repair were not so high, the mainboard was oxidyzed in many spots but I made a nice cleaning, resoldering and component replaging work and now it is almost working.

            Among other things I've cleaned many spots from oxyds, reballed CPU, EMMC, EC, replaced...
            05-07-2025, 06:10 AM
          • Loading...
          • No more items.
          Working...