[DarkPassenger]

Computer suddenly shut off and when testing new power supply before installation I hooked up case fan and the lights come on but the fan does not turn. Its a little Logisys. I guess my question is, could this have killed the PSU from overheating? Could the fan just not be on because its not hot? Is it common for the fan to go out but not the lights? Thanks!

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Hi DarkPassenger, and welcome to Geeks to Go!

 

The case fans really aren't meant to keep the PSU cool. The PSU is enclosed in its own metal housing will have its own internal fan. It should be visible if you look through the back of the PSU. The case fan is really for internal components such as (but not limited to) RAM, hard disks, graphics cards (at least the ones without their own fans), etc. If the lights are on but the fans are not spinning then I suspect that the BIOS has not determined it to be necessary - some fans only spin when the temperature reaches a threshold. Did the fan previously spin at boot before you swapped the PSU? Does the system boot?

 

In short, I do not suspect the PSU to have been damaged by the case fan ceasing to work, but I need more information to accurately answer your question regarding whether or not the case fan is supposed to spin at boot.

 

Good luck 

[Facedown98]

Hi DarkPassenger, and welcome to Geeks to Go!

 

The case fans really aren't meant to keep the PSU cool. The PSU is enclosed in its own metal housing will have its own internal fan. It should be visible if you look through the back of the PSU. The case fan is really for internal components such as (but not limited to) RAM, hard disks, graphics cards (at least the ones without their own fans), etc. If the lights are on but the fans are not spinning then I suspect that the BIOS has not determined it to be necessary - some fans only spin when the temperature reaches a threshold. Did the fan previously spin at boot before you swapped the PSU? Does the system boot?

 

In short, I do not suspect the PSU to have been damaged by the case fan ceasing to work, but I need more information to accurately answer your question regarding whether or not the case fan is supposed to spin at boot.

 

Good luck 

[DarkPassenger]

I'm not 100% sure if the fan was spinning before the PSU went bad. It's my son's. I have it all together now but I haven't booted yet. I have been debating with myself if I should put the case fan back in. I wasn't sure if it not working would draw unhealthy power. I question like you if it needed some signal that it was hot for it to kick on. It doesn't plug into the motherboard at all, just the PSU. As I'm sure you can tell im new at all this. Everything I know I've learned from the web. I'm loving this site and I really appreciate your help. Now that my son is into PC gaming im sure I'll be here alot. So in your opnion am I ok to go ahead and hook up the fan before I finish up and reboot? Oh and the blades move when I push them but not freely like the graphics card and CPU fans. Many thanks!!

[Facedown98]

You're very welcome and we're glad to help! You're doing fine.

 

I would recommend re-installing the case fan. Go ahead and reconnect it just as you found it. Different computer manufacturers and models have different configurations. Some will always run the fan so long as it has power, and others will only activate the fan when a temperature threshold is met. The fact that it connects to the PSU directly indicates that it should always be running. A fan connected directly to the motherboard would indicate that it is regulated by the board.

 

Can you please clarify whether the lights you mentioned are on the fan or somewhere else? It would be unusual for a fan to have lights on it, but some computers (especially those made for gaming) will use them for aesthetics. Are there other case fans? Do they work?

 

When you mention the fan blades not spinning freely, does it feel like there is a spring or something that returns the blades to a particular position? It's difficult to explain, but most fans I have encountered will spin if you lightly flick them with your finger, but after a couple of seconds, you see them stop at the same position you started at. A "free moving" fan would spin for much longer I suspect. Does that sound like what you have noticed?

 

I suggest putting the case fan back in and connecting it the same way you found it. Power-on the PC and see what happens. The BIOS may display an error if it cannot communicate with the fan, or it may be simply ignored. Leave the system on for a short time and even try using it. See if the fan spins up after a bit. The worst case scenario is that Windows will shut down the system and display a "blue screen" (affectionately known the Blue Screen of Death (BSOD). If that happens, don't panic - we're half expecting it. One time won't hurt the system but prolonged heat exposure could damage some components. When you check to see if the fan is running, place your hand on the outside of the case and see if it is hot to the touch. A little warmth is fine, but it shouldn't be hot necessarily. If it feels hot or starts to smell strange, then power the system down immediately. That's an extreme scenario but knowledge is power, right?

 

Let us know how it turns out.

[DarkPassenger]

The lights are on the fan. It was bought as a gaming computer. The blades don't move with a flick. I know what you mean, its the way the graphics card and CPU fans move. No, there are no other case fans. I will go ahead and hook it up and boot. I let you know how it goes. Thanks again!

[Facedown98]

Ok, very good. I would not worry about the fan not moving freely then - It sounds normal to me. The lights on the fan are a good indication that it is receiving power. We'll look forward to hearing from you.

[DarkPassenger]

Ok. Its the morning after and I want to go ahead and clean this up for anyone who might find this useful. First to clarify that last point. The case fan was not moving freely and the other fans were moving freely. And I now know that fan was definitely bad. Getting power but the bearings are bad. I got it all hooked up and booted and all seemed well, but the fan was still lighting up but not spinning. I had my son start up a game and within 10 minutes, shutdown. My first thought was, oh no, not another PSU. So I unplugged the fan let it sit for a few minutes and hit the power button. It came right back on no problem. Started a game, 10 minutes....shutdown. So I start reading about overheating, and shutdowns, and on and on, the whole time thinking how could this little piece of crap fan be so important. So I downloaded HWMonitor. It tells you the temperature of CPU, motherboard, graphics card and what not. Lots of other numbers on there that im sure are helpful to somebody that knows what the heck they are doing. So im watching that on the second monitor while my son plays his game and of course everything was getting hotter and then....shutdown. The CPU looked like it was in acceptable range but the graphics card which is a lower end model got to 70°C and I believe that was causing the shutdown. So I opened up the case, pointed a small box fan at it and tried again. Ran smooth in game never getting over 55°C and never shutting down. So what do you know, that little fan is pretty important. So, not wanting to leave the case open with a fan pointed at it, which im sure an expert would cringe at me having done, I ran staight to best buy. 10 bucks, 3 speed, blue led lights. And I did confirm, as my new friend here, Facedown98, pointed out, that just hooking straight to the PSU with molex means fan is always on. There was another plug with this new fan that I assume goes to the motherboard but I couldn't fine a place on mine. Soooo, I get it hooked up, boot up, start a game, and monitor the heat. GSU never got over 41°C. Almost 15° cooler than with the side off and a fan pointed straight in. Go figure. So what I learned, case fans are important if your gaming on your computer. As for the original topic where this all started. I believe Facedown98 is right, the bad case fan didn't directly make the he PSU go out. As I saw, no fan caused the temp to rise and the computer to shut down, but didn't affect a good, new, working PSU. The only thing I can think is that the PSU was already faulty, or just plain crappy, and when the original fan went out, the temp went up and the computer shut down. Maybe PSU shorted or some such thing? At any rate, we are finally good. Thank you Facedown98 and geeks to go. I love this site, and seeing as I have about 8 months to build my son a better gaming computer for his birthday, you'll be hearing from me again. I have MUCH to learn.

[Facedown98]

Good morning! Thanks for your feedback and for posting a detailed summary of your experience! You've done pretty well but don't hesitate to start a new topic in the system building forum if and when the time comes to build a new system. We're happy to help.

 

Best of luck and we'll see you around!