Fixing a PSU fan
Fixing a PSU fan
If you're thinking about swapping the fan, begin by searching YouTube for instructions specific to the exact power supply you own. There could be several versions of the VS650 available. However, my suggestion is to replace the whole power supply unit. It seems you might not be following that advice. Good luck!
Thank you for your advice, and sorry for being stubborn. I'll stay up all night and think about it again tomorrow.
Dude, those fans are sealed bearings. It’s unlikely you can just spray WD-40 and lubricate them. You might be able to swap it out if the housing isn’t sealed and you can open it, but even then, you’d need precise knowledge—and from what I’ve heard, you’re more likely to get hurt than fix it. Those power supplies are available on Newegg for $80. Is it worth risking your safety?
I chose to listen to you and didn’t open the PSU. Instead I tried poking the fan inside with a small wooden stick to see if it affected the noise. I put the PSU back in place and restarted the PC, but another error appeared.
My PC won’t let me log in. On the start screen it says “Preparing Windows for automatic repair” and “diagnosing computer” (my language settings are not English, so translations might be inaccurate).
It keeps looping when I try to restart, and I have no idea what to do next. Any possible solutions?
It seems Windows has repeatedly failed to start and has initiated an automatic repair process. You may allow it to try fixing itself automatically; success varies. Look for "fixes" in the log when the automatic repair fails. If that doesn’t work, consider booting from a Windows installation USB drive matching your system version on the hard drive, and select the Update option. This will reinstall Windows while preserving your files and programs (if possible).
It’s advisable to remove the faulty drive, connect it to another machine, and back up all data before attempting an update. A standard clean install would erase everything.
Regarding the fan issue, it's a straightforward job for someone skilled. If you have a pattern of damaging repairs, avoid handling this yourself—seek professional help instead.
There are indeed extremely high voltage levels above the SELV limit inside an ATX power supply when powered on, which can cause electrocution if not handled carefully. However, disconnecting the mains and briefly holding the power button can safely discharge the 420V bulk capacitor. As long as you avoid touching exposed wires or uninsulated ends for several hours, the risk of injury is low.
If concerned, wearing thick gloves is a good precaution. I recall working on valve TVs where the chassis was sometimes connected to mains voltage (240V AC). It’s wise to start with basic knowledge—many fatalities occur in car crashes or gun accidents rather than from ATX PSUs. Even one electrocution is unacceptable, but life carries risks.
The two fan wires may connect to a small white 2-pin connector on the main PCB. The connection point might be covered by glue to prevent the wire from detaching, making it harder to remove. Alternatively, the wires could be soldered directly onto the board. Record where they are before unsoldering. Note any labels inside the hub that indicate the airflow direction.
After removing the fan from the PSU, test it on another ATX PSU’s 5V supply (red +5V and black 0V). If it spins fast, it’s a 5V fan; if slow, likely 12V. Connect to the 12V supply on a Molex connector (yellow +12V, black 0V) for proper speed control. The PSU adjusts voltage to regulate fan speed.
I often remove dead fans from old units for reuse as spares or case fans—they usually run at 12V. You can purchase fans with the correct small white connector already attached. If you have a fan rated for 12V, cut the plug and solder the appropriate wires to the 2-way connector removed from the old fan.
For more details, see: https://superuser.com/questions/1126136/...difference
Reassemble the PSU after removing the fans, ensuring the label on the hub faces the correct direction. Spin the blades to confirm they move freely. Reattach the PSU PCB carefully, avoiding bending or crushing wires. Give it a try and power it up.
Some PSUs require at least 250W before the fan starts; others activate immediately.
TLDR: Fans from dead PSUs can be replaced if you’re skilled, but dangerous voltages may remain inside after unplugging. If unsure or inexperienced, avoid handling the unit yourself.
I appreciate we shouldn't encourage all and sundry to open their PSUs, but snatu's plan of action (see below) shows a good grasp of what needs to be done and the risks involved (see step 2.) and it was obvious he was intending to open the PSU without being prompted by forum members.
So here is my plan:
1. Opening the side panel, disconnecting all of the cables attached to the back of the PC.
2. Discharging the capacitors in the PSU by holding the power button for 20sec, repeating this 3 more times and waiting overnight.
3. Taking the PSU out of the case and opening it (I am planning to leave the wires for components connected to the motherboard because I dont want to mess up the cable management, let me know if this is bad for the PC)
4. Taking the fan out of the PSU
5. Applying sewing machine oil for the bearing and putting everything back in place.
Here is another statement by snatu which gives me confidence he has an excellent grasp of the hazards involved.
And yes, I might be a little underqualified, but I dont need a degree in electrical engineering to know that its the capacitors being the safety hazard, and therefore its not generally a good idea to open the PSU. But if they are completely drained, there is no safety hazard anymore, right?
I would not have described in detail how to proceed, had snatu not produced exactly the same method I would have used, apart from oiling the fan. Mind you, I've just oiled the bearings of the ailing fan motor in my fridge/freezer, so perhaps it wasn't such a bad idea.
I've met many unqualified engineers and mechanics in third world countries who have far more experience than I, but who knows how many of their associates were injured learning their trade?
If he was certain about what he was doing, they would never have posted here. For those with years of experience, this is the one rule to always follow. We don't assist with piracy, bypassing passwords, or encouraging actions that pose a serious risk.
I am familiar with only one individual from the 1970s who passed away after disabling the safety interlocks on a 10,000V 2.5A DC power supply in a 25kW power supply for a MIL-SPEC 10kW RF Linear Amplifier. I recognize the risks associated with handling high voltages.
The impact of the shock propelled him out of the lab and he could not be revived. He would have been wise to avoid interfering with the interlocks.
Moving forward, I will refrain from giving unsolicited guidance on high-voltage projects above the SELV limit in any forum.