Corsair GS800 fan spinning only on boot

[DS-1]

Hi guys!

I have this PSU that I've bought used.

The fan spins at max when computer boots, then there's a very high frequency sound coming from PSU and the fan doesn't spin anymore, even if I try to push the computer using stress tests utility like PRIME95 or AIDA64.

Sometimes the fan seems to try to start, but eventually it doesn't.

I know this is a very common issue for this PSU, but I've found no fix for it (someone used a new fan controlled by mb header, but I'd like to know if it's fixable to be used as it is stock).

Thanks in advance for the reply!

[sam_sam_sam]

Re: Corsair GS800 fan spinning only on boot

Post some pictures of this power supply board front and back of the board

[DS-1]

Re: Corsair GS800 fan spinning only on boot

Post some pictures of this power supply board front and back of the board

Here are the pics:









I've made also pics to the smaller board screwed on the panel.

[Per Hansson]

Re: Corsair GS800 fan spinning only on boot

This is a fanless PSU at low loads.
What is the power consumption on the PSU when you say it is under heavy load by Prime95?
Remember it is an 800w PSU and most desktop machines will be hard pressed to pull 200w DC.
If it is not getting hot to the touch I would say it is working as intended.

[DS-1]

Re: Corsair GS800 fan spinning only on boot

This is a fanless PSU at low loads.
What is the power consumption on the PSU when you say it is under heavy load by Prime95?
Remember it is an 800w PSU and most desktop machines will be hard pressed to pull 200w DC.
If it is not getting hot to the touch I would say it is working as intended.

Thanks for the reply.

I knew that it is fanless when the load is low. What makes me think about a fault was the fact that, after a while, the fan seems to start to spin, but it moves only a bit. Also, the PSU makes a very high pitch sound that seems to be something faulty.

I have a i5 8500 with a h370m board and. a RX570 double fan (and double PCI e molex) and a 3.5" hdd.

Is there any way to test how much power it consumes when under PRIME85 test?

[Per Hansson]

Re: Corsair GS800 fan spinning only on boot

The CPU has a TDP of around 65w
Intel cheats a bit in their TDP specs so it can draw more than that.
In general the system will draw around 100w DC during Prime95
The GPU has a TDP of 120w, it can draw around 170w or so during gaming.
In total around 200w DC or 25% of what the PSU can deliver.

You can use an inline power meter, in the US they are called "Kill A Watt"
In Europe it is more common with German brands like Voltcraft for example.
Or you can use a multimeter in amps mode, but you need to cut the 230v cable in two to do it so not very safe...

Download Superposition benchmark and run that instead of Prime95, should be a much tougher load.
But still remember that it will only be max ca 25% of what the PSU can actually deliver...
https://www.techspot.com/downloads/7...rposition.html

[DS-1]

Re: Corsair GS800 fan spinning only on boot

The CPU has a TDP of around 65w
Intel cheats a bit in their TDP specs so it can draw more than that.
In general the system will draw around 100w DC during Prime95
The GPU has a TDP of 120w, it can draw around 170w or so during gaming.
In total around 200w DC or 25% of what the PSU can deliver.

You can use an inline power meter, in the US they are called "Kill A Watt"
In Europe it is more common with German brands like Voltcraft for example.
Or you can use a multimeter in amps mode, but you need to cut the 230v cable in two to do it so not very safe...

Download Superposition benchmark and run that instead of Prime95, should be a much tougher load.
But still remember that it will only be max ca 25% of what the PSU can actually deliver...
https://www.techspot.com/downloads/7...rposition.html

Yes, I was thinking about the second option (cutting the 230v cable and use the multimeter in Ampere).

I've found that a lot of GS series users have the issue of the fan that seems to start spinning, but no one talk about a real fix for it. Maybe they didn't know about the silent mode?

[eccerr0r]

Re: Corsair GS800 fan spinning only on boot

In the EU you can cut a mains cable and use an AC ammeter.

Can't do the same in the USA... since there's no requirement for USA computer equipment to have high power factor... BOOO...have to get a true RMS ammeter...

[DS-1]

Re: Corsair GS800 fan spinning only on boot

In the EU you can cut a mains cable and use an AC ammeter.

Can't do the same in the USA... since there's no requirement for USA computer equipment to have high power factor... BOOO...have to get a true RMS ammeter...

I will try in the next days and I'll let you know how the test goes...

[DS-1]

Re: Corsair GS800 fan spinning only on boot

I have to say that GS800 is working fine: I've tested it on an older machine (p8h61-m le with 4 cores i5 2400 and a HD7870 with dual PCI-E connectors) and, when launching benchmarks, the GS800 fan starts to spin!

The only thing that is strange is that, after 2-3 minutes of benchmark, the fan wants to start, but it's buzzing. After 5 or more minutes, it starts to spin without issues. Maybe there are some problems when, after 2-3 minutes, the temperature is not that high and so it should spin at lower rpm.

[PeteS in CA]

Re: Corsair GS800 fan spinning only on boot

This is a fanless PSU at low loads.
What is the power consumption on the PSU when you say it is under heavy load by Prime95?
Remember it is an 800w PSU and most desktop machines will be hard pressed to pull 200w DC.
If it is not getting hot to the touch I would say it is working as intended.

In some server PSUs, especially those rated "Platinum" or "Titanium", the fan spins at full speed for several seconds after the PSU is enabled, and then drops to low speed or stops until something inside gets hot enough to require additional cooling. I think this may be either a start-up default or to cool the auxiliary/standby regulator after having been in standby mode for an extended time period. Or both. Fans require power, and when a PSU is rated for >95% efficiency, the power to run the fan can be relevant.

[DS-1]

Re: Corsair GS800 fan spinning only on boot

In some server PSUs, especially those rated "Platinum" or "Titanium", the fan spins at full speed for several seconds after the PSU is enabled, and then drops to low speed or stops until something inside gets hot enough to require additional cooling. I think this may be either a start-up default or to cool the auxiliary/standby regulator after having been in standby mode for an extended time period. Or both. Fans require power, and when a PSU is rated for >95% efficiency, the power to run the fan can be relevant.

Corsair says that this GS series (but I believe some other PSUs, too) work in this way: fan starts to spin when there is a load of almost 250w.

The strange thing is that mine would like to spin I think even in "normal" use (not in game or during benchmarks), but the fan has a sort of "faulty start" with a buzzy noise. When the load increases, fan starts. That's why I'm not sure if my PSU works correctly or not!

[momaka]

Re: Corsair GS800 fan spinning only on boot

This might be a silly question, but can the fan actually spin freely?
In other words, if you spin it by hand, does it take a while to come to a stop (and do a little "wobble" when it finally stops)? Or does it stop rather quickly? If it's the latter, the fan might need a bearing cleaning (if it's a sleeve bearing fan) or bearing replacement (if it uses a BB).

I also can't help but notice the PSU has green electrolytic caps on the output, which if I'm not mistaken would be either Taicon or Samxon. Whichever the case, those would be "2nd tier" caps, and I would suggest you modify the fan circuit in the PSU to have the fan run all the time. The easiest way to do that, if it's a 2-pin fan (most are) would be with two diodes on the positive (red) wire of the fan: one diode feeding the fan constant 5V when the PSU is on, and the other diode feeding power from the fan regulator circuit, so that if the PSU wants to run the fan at a higher speed for some reason, it can still do that.

[DS-1]

Re: Corsair GS800 fan spinning only on boot

This might be a silly question, but can the fan actually spin freely?
In other words, if you spin it by hand, does it take a while to come to a stop (and do a little "wobble" when it finally stops)? Or does it stop rather quickly? If it's the latter, the fan might need a bearing cleaning (if it's a sleeve bearing fan) or bearing replacement (if it uses a BB).

I also can't help but notice the PSU has green electrolytic caps on the output, which if I'm not mistaken would be either Taicon or Samxon. Whichever the case, those would be "2nd tier" caps, and I would suggest you modify the fan circuit in the PSU to have the fan run all the time. The easiest way to do that, if it's a 2-pin fan (most are) would be with two diodes on the positive (red) wire of the fan: one diode feeding the fan constant 5V when the PSU is on, and the other diode feeding power from the fan regulator circuit, so that if the PSU wants to run the fan at a higher speed for some reason, it can still do that.

Yes, fan can easily moves if I spin it by the hand, that's why I supposed there's something "wrong" in the automatic fan spinning circuit.

I could do the modify you suggested. I'll write here when I'll realize it!

Thanks!