Help with hissing noise!

ghop · 21 Jan 2010 at 21:54

I got an i5 and a P55A-UD3 the other day, and when the CPU temperature goes above 80 or so, a hissing noise, a bit like bacon cooking eminates from around the CPU area. My first thought was sizzling thermal paste, which seems a bit unlikely, second thought was that it was a capacitor and lastly I thought it may be the heatpipes.

It's quite a low hissing and I only heard it when the side was off the PC. I wasn't too worried at the time but now I'm getting really paranoid, thinking it's a leaking capacitor that's going to take out my motherboard and my CPU.

Is it anything to worry about?/what is it? I'm thinking it's something on the motherboard making the noise which worries me, as it's brand new and nothing is supposed to make a noise really. I need to know if I need to RMA it, if I do, what a pain! It's only above a pretty high temp and other than hissing everything runs fine.

hubby1989 · 21 Jan 2010 at 22:12

Firstly, why on earth is an i5 going above 80oC!!?? What cooling unit have you got on the i5?

ghop · 21 Jan 2010 at 22:25

I was at 1.425v stress testing 4ghz in IBT and it was getting rather hot. At the moment I'm at 3.8ghz 1.325v and load temps aren't exceeding 60 in Prime95 and 50 under normal load.

I'm running a CM 212 Plus.

But anyway, what could be causing the hissing and is it a cause for concern?

EDIT: And I haven't heard it since the stress testing at 4ghz.. I think it's to do with the high temperatures.

kidscruff · 21 Jan 2010 at 22:45

Could it have been a capacitor near the CPU?

ghop · 22 Jan 2010 at 00:17

kidscruff said:
Could it have been a capacitor near the CPU?

That's what I'm thinking, but does it mean this capacitor is on its way out? That it didn't like the heat? I don't know a lot about capacitors but from what I've read, they're not supposed to hiss. I want to know otherwsie I'll be constantly fearing my motherboard is going to blow up.

AMG · 22 Jan 2010 at 00:27

only way to find out is to take a close look at all your caps

if one looks "expanded as in like a bollon" than you in **** street, it may involve taking heatsinks off through :S which in tern voids warranty unless you put them back on properly with no damage

neblemak · 22 Jan 2010 at 00:52

I once had a 4850 that made a similar sound to the one you're describing under load, that was caps as I recall.

If it only happens when stress testing at 4ghz, I doubt you've caused any permanent damage but that your caps are 'stressed'. If it were me I'd back it down a bit and call that the limit of my current setup.

ghop · 22 Jan 2010 at 01:06

AMG said:
only way to find out is to take a close look at all your caps

if one looks "expanded as in like a bollon" than you in **** street, it may involve taking heatsinks off through :S which in tern voids warranty unless you put them back on properly with no damage

neblemak said:
I once had a 4850 that made a similar sound to the one you're describing under load, that was caps as I recall.

If it only happens when stress testing at 4ghz, I doubt you've caused any permanent damage but that your caps are 'stressed'. If it were me I'd back it down a bit and call that the limit of my current setup.

Yeah, I've found my sweet spot now

3.8ghz and under full load, no hissing! I just want to make sure I haven't caused permanent damage, or if my motherboard is faulty and at risk of taking out my CPU.

I'll take a close look at the caps tomorrow. It might mean removing my CPU cooler, but I want to reseat anyway. What I'm worried about is if the hissing means that the cap is definitely damaged.

SMAndy · 22 Jan 2010 at 08:20

Maybe, maybe not. Some capacitors have been known to expand and contract quite rapidly at certain frequencies (it's to do with the voltage frequency. Shouldn't be affected by the cpu speed, but then why does it ever happen?) It doesn't damage them, but it will stress them to death faster.

Most GTX260 cards have a bit of a whine at certain FPS (to do with how fast the memory is being accessed, i think) But it's nothing to worry about.

As for reseating the cooler, do you have any thermal paste around? It is highly inadvisable to reuse the existing stuff. Always clean off and re-apply.

ghop · 22 Jan 2010 at 12:00

What do you reckon I should do then? Leave it and hope for the best, or request an RMA?

And it only happened when the the temperatures went above about 80-85, and they only went above 80-85 when I had the volts up at 1.4ish.

Pauljl · 22 Jan 2010 at 12:25

if it is a component burning out, you should be able to smell it...

its not easy to put into words how it smells, but im sure you would realise if it was..
the smell gets you right at the back of your throat

kidscruff · 22 Jan 2010 at 12:31

If it's working fine, then it's unlikely an RMA will be an easy option. Most likely it will be tested and returned to you.

If you tell them you're returning it because it's hissing at 80+ degrees, I presume they'll ask you what on earth are you doing at 80+ degrees!

It's possible capacitors can get too hot (normally through overvoltage or reverse polarity) and effectively boil off the electrolyte contained within - which might explain the hissing noise. You can tell if it's really bad as the capacitor top will bulge out.

I would say it's probably fine, now that you're running back down at 3.8GHz. Keep an eye on it, and if it stops working in the next couple of months then RMA your board.

ghop · 22 Jan 2010 at 12:46

Pauljl said:
if it is a component burning out, you should be able to smell it...

its not easy to put into words how it smells, but im sure you would realise if it was..
the smell gets you right at the back of your throat

Thanks, I'll be opening my PC up soon and checking for bulging and that smell. Gives me a reason to reseat my heatsink too

kidscruff said:
If it's working fine, then it's unlikely an RMA will be an easy option. Most likely it will be tested and returned to you.

If you tell them you're returning it because it's hissing at 80+ degrees, I presume they'll ask you what on earth are you doing at 80+ degrees!

It's possible capacitors can get too hot (normally through overvoltage or reverse polarity) and effectively boil off the electrolyte contained within - which might explain the hissing noise. You can tell if it's really bad as the capacitor top will bulge out.

I would say it's probably fine, now that you're running back down at 3.8GHz. Keep an eye on it, and if it stops working in the next couple of months then RMA your board.

The thing I'm worried about is if it goes and takes out the motherboard AND the CPU. If this happens, can I RMA both?

I'm going to open up my PC and have a good look now, perhaps take a few pictures

I'll report back what I see.

kidscruff · 22 Jan 2010 at 12:49

Both CPU and Motherboard from the same supplier? When I found my motherboard CPU socket faulty, the shop requested both motherboard and CPU back to test. CPU they said was fine (guess they just booted it and it worked), but Motherboard needed replacement.

ghop · 22 Jan 2010 at 15:15

Took a couple of pictures of the capacitors closest to the CPU (with great difficulty, couldn't find my Isopropyl Alcohol so I decided not to reseat the heatsink) and they 'look' fine, but then again I don't know what to look for. No dodgy smell either but I'm guessing that would have dissipated long ago anyway..

I'm thinking it's maybe more to do with Voltage than heat now, because it was as soon as the 100% load went on the CPU, and stopped instantly after the load was taken off. How long does OCUK let you RMA for? And yes, I bought all 3 items off of OCUK

Sayso · 22 Jan 2010 at 19:12

Pauljl said:
if it is a component burning out, you should be able to smell it...

its not easy to put into words how it smells, but im sure you would realise if it was..
the smell gets you right at the back of your throat

Fish...ive blown plenty when i was a PCB tester in my younger days

ghop · 22 Jan 2010 at 20:40

There's no fishy smells and I can't see any bulging capacitors. Does this mean my mobo is in the clear? I really need to put my mind at rest

Thanks for all the advice so far btw.

BUFF · 22 Jan 2010 at 22:22

kidscruff said:
It's possible capacitors can get too hot (normally through overvoltage or reverse polarity) and effectively boil off the electrolyte contained within - which might explain the hissing noise. You can tell if it's really bad as the capacitor top will bulge out.

doesn't the UD3 have solid caps though so no electrolyte?

ghop · 22 Jan 2010 at 23:35

BUFF said:
doesn't the UD3 have solid caps though so no electrolyte?

They are indeed all solid. I don't know anything about capacitors so assumed they all had electrolyte in them

. Is it possible that solid caps can make a hissing noise?

MikeHunt79 · 22 Jan 2010 at 23:50

ghop said:
They are indeed all solid. I don't know anything about capacitors so assumed they all had electrolyte in them . Is it possible that solid caps can make a hissing noise?

Those look like Sanyo OS-CON caps which are computer grade caps which use some sort of organic compound I think, which is supposed to be more durable than a normal electrolyte cap.

They should not hiss however...