Question Newly built PC runs fine but I've noticed a burning smell ?

[Lucerp]

About a week ago I built a new PC with completely new parts. It booted up nicely, and it has been running perfectly for the whole week. However, yesterday I noticed a weird burning smell (almost like an exploded firework smell). It was very subtle, but definitely noticeable when I smelled near the top exhaust fan of the PC. I was worried and wasn't sure what to do, and eventually, the smell became pretty bad suddenly so I turned off the PC (this smell hasn't returned since). I have looked everywhere, all capacitors look fine, all connectors seem okay, I couldn't pinpoint the smell because it would fade away after turning off the PC. Today I stress tested the GPU, CPU and RAM and all run totally fine with good temps (40 idle and around 60 during stress test). I just unplugged the PSU and noticed that the 24 pin ATX cable smells really bad after unplugging it from the PSU. The smell only remains for a short while, but the other cables don't smell like this.

Is this okay?
Do I get a new PSU?

Specs:
CPU - Ryzen 7 5800x
GPU - Asus TUF RTX 3070 ti
MB - msi mag x570 tomahawk wifi
RAM - 32 gb 3600 MHz
Cooler - NZXT Kraken X63
PSU - Corsair RM 750x
Case - NZXT H510 Flow
Storage - Samsung 970 Evo Plus 2 TB

 

[Fix_that_Glitch]

RMA the psu immediately. Inspect the atx slot to make sure nothing is burnt, melted or pins not strait. Take pictures of any visible damage to your psu atx cable and atx slot for your protection.

 

[Fix_that_Glitch]

Sorry forgot to add if you find damage to your atx slot do not use the motherboard. Contact the support for the motherboard and determine how you should go about replacing the motherboard. Will they honor the warranty if the psu caused the damage, or will you have to go after the psu maker.

 

[Lucerp]

Sorry forgot to add if you find damage to your atx slot do not use the motherboard. Contact the support for the motherboard and determine how you should go about replacing the motherboard. Will they honor the warranty if the psu caused the damage, or will you have to go after the psu maker.

Thanks for the quick reply. I have checked again multiple times and the smell is not as present as before, and I can see no damage. Instead of a firework smell, there is currently a subtle metallic smell. I assume you still want me to RMA the PSU right?

 

[Fix_that_Glitch]

Thanks for the quick reply. I have checked again multiple times and the smell is not as present as before, and I can see no damage. Instead of a firework smell, there is currently a subtle metallic smell. I assume you still want me to RMA the PSU right?

Absolutely RMA it, there should be zero smells of any kind. Did you install the offsets when you installed the motherboard (They help grounding the motherboard)? A smell of any kind coming from wiring or psu is a definite sign of a problem and should not be taken lightly. You could lose all your components and at the worst suffer a fire.

 

[Lucerp]

Absolutely RMA it, there should be zero smells of any kind. Did you install the offsets when you installed the motherboard (They help grounding the motherboard)? A smell of any kind coming from wiring or psu is a definite sign of a problem and should not be taken lightly. You could lose all your components and at the worst suffer a fire.

The case came with the offsets installed. I am not sure if I will be able to RMA the PSU, since I ordered it from Amazon and then my housemate threw the packaging away. According to Amazon policy, it requires the original packaging.

 

[Fix_that_Glitch]

The case came with the offsets installed. I am not sure if I will be able to RMA the PSU, since I ordered it from Amazon and then my housemate threw the packaging away. According to Amazon policy, it requires the original packaging.

Well I'm no Amazon expert, wouldn't hurt to ask them. Perhaps if you register the psu warranty you can go that route. Either way I strongly recommend a new psu. But it is your choice.

 

[Lucerp]

Well I'm no Amazon expert, wouldn't hurt to ask them. Perhaps if you register the psu warranty you can go that route. Either way I strongly recommend a new psu. But it is your choice.

I'll do my best to try to get the warranty for it, but if I can't then I'll just buy a new PSU. The only thing now is I'm worried the motherboard is also damaged. Yesterday I let the PC run lightly so I could try to finally pinpoint the smell, and it started to smell a bit like cigarette smoke, which I'm guessing is just straight up smoke. I still didn't see any smoke, but I'm scared something on the motherboard is burnt (honestly I really don't want to go through the pain of replacing the motherboard). I attached a couple of photos of marks on the PSU cables that connect to the motherboard, but I'm not sure if they're due to burns. If these are what was causing the smell, then hopefully the motherboard is safe.
https://drive.google.com/file/d/1bUfkzJH8kUuaRzI00fx9N51qKKmDW9Yt/view?usp=sharing
https://drive.google.com/file/d/17qXZlfiIT9sPEOqAlVTCmP-WYnVF2tyP/view?usp=sharing

 

[geofelt]

Sometimes, a new piece of electronic equipment can hive off a smell from solder flux burning off.
I doubt that is the case here.

RMA the unit directly with Corsair customer support.
The serial number will lead to date of manufacture and possible issues with that run.

Such units will have at least a 7 year warranty.
Proof of purchase is not likely to be needed, but your Amazon invoice should suffice if necessary.

One possible cause is a defect in the psu cable or the motherboard connector.

 

[Lucerp]

Sometimes, a new piece of electronic equipment can hive off a smell from solder flux burning off.
I doubt that is the case here.

RMA the unit directly with Corsair customer support.
The serial number will lead to date of manufacture and possible issues with that run.

Such units will have at least a 7 year warranty.
Proof of purchase is not likely to be needed, but your Amazon invoice should suffice if necessary.

One possible cause is a defect in the psu cable or the motherboard connector.

If it's a defect in the motherboard connector, would I need to RMA the motherboard as well?

 

[geofelt]

If it's a defect in the motherboard connector, would I need to RMA the motherboard as well?

Yes, but you may get some push back since damage to the connector can be user caused.
More likely the problem lies with a short withing the psu power lead.

 

[Lucerp]

Yes, but you may get some push back since damage to the connector can be user caused.
More likely the problem lies with a short withing the psu power lead.

Should I try to RMA the motherboard now just to be safe or should I wait for when I have a new PSU to see if the problem persists?

 

[Fix_that_Glitch]

I'll do my best to try to get the warranty for it, but if I can't then I'll just buy a new PSU. The only thing now is I'm worried the motherboard is also damaged. Yesterday I let the PC run lightly so I could try to finally pinpoint the smell, and it started to smell a bit like cigarette smoke, which I'm guessing is just straight up smoke. I still didn't see any smoke, but I'm scared something on the motherboard is burnt (honestly I really don't want to go through the pain of replacing the motherboard). I attached a couple of photos of marks on the PSU cables that connect to the motherboard, but I'm not sure if they're due to burns. If these are what was causing the smell, then hopefully the motherboard is safe.
https://drive.google.com/file/d/1bUfkzJH8kUuaRzI00fx9N51qKKmDW9Yt/view?usp=sharing
https://drive.google.com/file/d/17qXZlfiIT9sPEOqAlVTCmP-WYnVF2tyP/view?usp=sharing

What is that black spot on the atx cable? Is that the spot that smells? Can you post a picture of what the atx cable is near on the motherboard? It may be touching something, and from the heat it generates can be causing something to melt on to it.

 

[rickypicky5]

When did you buy the PSU and was it new when you bought it?

Is the 24 pin cable you're using the cable that came with the PSU?

 

[Lucerp]

What is that black spot on the atx cable? Is that the spot that smells? Can you post a picture of what the atx cable is near on the motherboard? It may be touching something, and from the heat it generates can be causing something to melt on to it.

There's nothing that close to the connector, and I don't see any marks or anything inside the connector.
https://drive.google.com/file/d/1VJxVK4GS5xLtzkXD68HtePeoS-mPqQIv/view?usp=sharing

20220502_162013.jpg

drive.google.com

https://drive.google.com/file/d/1XfLejIKtcuWBArDkEp7ot1J1bf_Ecu4g/view?usp=sharing

 

[Lucerp]

When did you buy the PSU and was it new when you bought it?

Is the 24 pin cable you're using the cable that came with the PSU?

I bought all the parts new in the middle of April, and yes the cable I used came with the PSU.