Common Issues/Questions

[Guest]

I find myself answering the same questions over and over again, so I put this together.  Also, a lot of times when these questions are asked, certain members jump in with "OMG! YUOR CAPACITORS ARE NOT JAPANESE AND ARE ON FIRE RETURN EMMEDIATELYLY!" and I get kind of sick of that.  If mods want to sticky, cool.  If not, I'll just reply to folks with a link to this thread. 

 

What is Coil Whine?

When current through the inductor changes, the magnetic field does as well. This causes a small attraction/repulsion action in the coils of the inductor, which manifests itself as a vibration/sound.

What is this white greasy stuff in my PSU?

PSUs use white thermal compound between components like MOSFETs and diodes and the heatsinks they mount to. 

 

What are these black markings on my connectors?

Cables are often tested to make sure they are pinned correctly. When the cable passes the test, it is marked with a Sharpie marker to show that it has been tested and passed.

 

What is this goo in my PSU?

This is RTV (room temperature vulcanizing) silicone. It’s a glue-like substance used to keep heavier parts in place on the PCB during transit. It is also sometimes used in magnetic components to help reduce coil whine. The color of the RTV can be white, black or gray.

 

Why does my PSU smell like it’s burning?

 

It`s normal for new Transformers to release some harmless odors from the varnish impregnation used in the coils for a week or two after energization. Older Transformers can also release some odor if loaded to a higher level than they have experienced previously in their history.

 

Why does my PC shock me?

 

If your mains are not grounded, there will be 3.5mA of power looking for a ground. When you touch a metal part of the PC, you become that ground. It’s perfectly safe, and normal, but you really should use a grounded outlet. 

 

Power supplies use “Y” capacitors connected from the neutral to ground as part of their integral EMI filter. These specially rated capacitors provide a low impedance path to the ground for high frequency noise to reduce EMI. 

 

Should I use PCIe pigtails for my graphics card?

 

The advice to not use pigtails is based on the assumption of worst-case scenario and should not be a blanket recommendation.  It's sort of like when Nvidia or AMD say you need a 1000W PSU when you can get away with a 750W.  They don't know the quality of your PSU and they don't know your rest of system.

 

The “weak link” in a cable is the terminal and not the wire gauge. The most commonly used 18g Mini-Fit terminals support 9A each. Some better PSUs use 16g HCS (High Current System) which supports 13A each terminal. 

 

This results in a 432W limitation for typical 8-pin 18g Mini-Fit connector terminals, and 624W for 8-pin connectors with 16g HCS terminals. Therefore, PSUs that use standard mini-fit terminals with 18g wire for their PCIe pigtail cables are not recommended for 450W+ cards. 

 

Most reviews by Aris Bitziopoulos have wire gauge reported in them. If you can find your PSU in a review, check the wire gauge table in the review. If not, when in doubt, opt for not using pig-tails. 

 

As I think of or run into more common issues/questions, I'll post them in this thread.

 

[BiotechBen]

27 minutes ago, jonnyGURU said:

I find myself answering the same questions over and over again, so I put this together.  Also, a lot of times when these questions are asked, certain members jump in with "OMG! YUOR CAPACITORS ARE NOT JAPANESE AND ARE ON FIRE RETURN EMMEDIATELYLY!" and I get kind of sick of that.  If mods want to sticky, cool.  If not, I'll just reply to folks with a link to this thread. 

 

What is Coil Whine?

When current through the inductor changes, the magnetic field does as well. This causes a small attraction/repulsion action in the coils of the inductor, which manifests itself as a vibration/sound.

What is this white greasy stuff in my PSU?

PSUs use white thermal compound between components like MOSFETs and diodes and the heatsinks they mount to. 

 

What are these black markings on my connectors?

Cables are often tested to make sure they are pinned correctly. When the cable passes the test, it is marked with a Sharpie marker to show that it has been tested and passed.

 

What is this goo in my PSU?

This is RTV (room temperature vulcanizing) silicone. It’s a glue-like substance used to keep heavier parts in place on the PCB during transit. It is also sometimes used in magnetic components to help reduce coil whine. The color of the RTV can be white, black or gray.

 

Why does my PSU smell like it’s burning?

 

It`s normal for new Transformers to release some harmless odors from the varnish impregnation used in the coils for a week or two after energization. Older Transformers can also release some odor if loaded to a higher level than they have experienced previously in their history.

 

Why does my PC shock me?

 

If your mains are not grounded, there will be 3.5mA of power looking for a ground. When you touch a metal part of the PC, you become that ground. It’s perfectly safe, and normal, but you really should use a grounded outlet. 

 

Power supplies use “Y” capacitors connected from the neutral to ground as part of their integral EMI filter. These specially rated capacitors provide a low impedance path to the ground for high frequency noise to reduce EMI. 

 

Should I use PCIe pigtails for my graphics card?

 

The advice to not use pigtails is based on the assumption of worst-case scenario and should not be a blanket recommendation.  It's sort of like when Nvidia or AMD say you need a 1000W PSU when you can get away with a 750W.  They don't know the quality of your PSU and they don't know your rest of system.

 

The “weak link” in a cable is the terminal and not the wire gauge. The most commonly used Mini-Fit terminals support 9A each. Some better PSUs use HCS (High Current System) which supports 13A each terminal. 

 

This results in a 432W limitation for typical 8-pin Mini-Fit connector terminals, and 624W for 8-pin connectors with HCS terminals. Therefore, PSUs that use standard mini-fit terminals with 18g wire for their PCIe pigtail cables are not recommended for 450W+ cards. 

 

As I think of or run into more common issues/questions, I'll post them in this thread.

 

Finally. 

[Vishera]

39 minutes ago, jonnyGURU said:

What is Coil Whine?

When current through the inductor changes, the magnetic field does as well. This causes a small attraction/repulsion action in the coils of the inductor, which manifests itself as a vibration/sound.

That's why coils are used as motors 

Also a side affect of that is a loss of efficiency since some of the power/energy is wasted by those vibrations.

 

I am pretty sure that thread will help a lot of people,and as always Jonny is very helpful ;D

[Guest]

1 minute ago, Vishera said:

Also a side affect of that is a loss of efficiency since some of the power/energy is wasted by those vibrations.

You are correct. And that energy is wasted as heat and that's why you can't completely caulk up a choke because it then stands the chance of overheating.

 

[dizmo]

+1 for stickying this.

I wish you had something in your profile to nod towards your proven expertise in the field. Maybe changing your Member tag under your username?

To show you're that jonnyGURU.

I'd alllllmost go as far as to say you'd be deserving of an Industry Affiliate tag. but tbh I'm not sure what you're up to these days.

 

Unrelated:

Spoiler

Can you get rid of coil whine? Or does it require PSU replacement?

I've already bought a new PSU to replace the whiny one, but curious for future builds.

 

[Vishera]

24 minutes ago, dizmo said:

Can you get rid of coil whine? Or does it require PSU replacement?

I've already bought a new PSU to replace the whiny one, but curious for future builds.

There is no gurantee that the new PSU will be coil whine free:

43 minutes ago, jonnyGURU said:

45 minutes ago, Vishera said:

Also a side affect of that is a loss of efficiency since some of the power/energy is wasted by those vibrations.

You are correct. And that energy is wasted as heat and that's why you can't completely caulk up a choke because it then stands the chance of overheating.

The vibrations make the noise that you call "coil whine" and as Jonny said the inductors get caulked up which helps minimizing the vibrations (which cause the coil whine).

My only experience with these stuff was at the Electronics class in high school so i have no clue if the inductors can break free off the caulk over x time of use.

[dizmo]

2 minutes ago, Vishera said:

There is no gurantee that the new PSU will be coil whine free:

The vibrations make the noise that you call "coil whine" and as Jonny said the inductors get caulked up which helps minimizing the vibrations that cause the coil whine.

My only experience with these stuff was at the Electronics class in high school so i have no clue if the inductors can break free off the caulk over x time of use.

Right, but there's an infinitely higher percentage of it being whine free, than if I left the current one in there

[Guest]

40 minutes ago, dizmo said:

Right, but there's an infinitely higher percentage of it being whine free, than if I left the current one in there

The problem in the industry is that we're trying to reach higher efficiency across a wider range of loads without really increasing switching frequency much higher than it was 20 years ago and that results in audible noise.  

[Cifer]

Very useful post, you should also have it on your personal website (in a more detailed version if possible).

 

9 hours ago, jonnyGURU said:

The problem in the industry is that we're trying to reach higher efficiency across a wider range of loads without really increasing switching frequency much higher than it was 20 years ago and that results in audible noise.  

Do you think it's possible to obtain a coilwhine-proof 80+gold PSU by increasing the switching frequency of an 80+titanium unit?

 

"Coilwhine proof" could become a selling point, especially if it's not covered by warranty (no such thing as zero risk) but still is backed-up by a badge of some sort (Cybenetics might be interested in creating a coilwhine scale). 

 

[Dogzilla07]

@CiferThere's a roundabout way to combat coil whine a bit. Faster spinning but not louder fans. Drown the coil whine in pure air wooshing noise. an LCP (Liquid Crystal Polymer) can spin a couple hundred RPM more for the same noise as a fan made from a normal material (even NB-ELoop Macrolon).

 

So you can use this to drown the noise a bit. MSI is the first to implement LCP fans in PSUs, their new ATX 3.0 PSUs come with their Silent Gale P12 fan (made by Power Logic). There's not enough testing, but so far it looks like it sacrifices a bit of performance for even better sound characteristics than previous record holders.

 

It's not gonna help that much (as the usual coil-whine frequency is gonna blast through anyway. but it doesn't hurt to do it (Power Logic is a huge OEM for fans [mostly GPU], so economies of scale will come into play as they produce more LCP fans).

[Guest]

4 hours ago, Cifer said:

Very useful post, you should also have it on your personal website (in a more detailed version if possible).

 

Do you think it's possible to obtain a coilwhine-proof 80+gold PSU by increasing the switching frequency of an 80+titanium unit?

 

"Coilwhine proof" could become a selling point, especially if it's not covered by warranty (no such thing as zero risk) but still is backed-up by a badge of some sort (Cybenetics might be interested in creating a coilwhine scale). 

 

Yeah.  You could, and then also have to improve how you combat the increased EMI, but then you're selling something more expensive with fewer bullet points (read: average customer ain't gonna buy it.)

 

I think a good happy medium solution is to use a thermally conductive potting material in lieu of RTV.   But it costs twice as much.  Still cheaper than re-engineering for higher switching frequencies, though.

[Mayrice]

Quote

Why does my PSU smell like it’s burning?

 

It`s normal for new Transformers to release some harmless odors from the varnish impregnation used in the coils for a week or two after energization. Older Transformers can also release some odor if loaded to a higher level than they have experienced previously in their history.

This gave me a fright a few days ago.

I loaded up that protein folding app for a combined stress test on my  GPU and CPU for the first time since I bought my RM750. Had me worried for a few hours.

Glad to know it can sometimes happen.

[rtyall]

Regarding EMI/RFI in a PSU, are there any easy ways to reduce or get rid of it?

 

I suspect (could be wrong though) that EMI from my PSU causes a high pitched buzz in my headphones, but only when playing some games and only on certain screens of games - the operator and weapon selection screen of COD Vanguard for instance. It was fine while I had a TX650M, I only noticed it after upgrading the PSU (upgraded due to GPU upgrade and was at the upper power threshold for my system).

 

I have an MSI MPG A850GF, I've added some ferrite chokes to the audio cables, they helped a bit. I've also found there's certain cable routes that decrease the buzz, but nothing gets rid of it fully.

[Glenwing]

 

There's just one thing I can't figure out...

Spoiler

HOW MANY WATTS DO I NEED??

 

[Guest]

4 hours ago, rtyall said:

Regarding EMI/RFI in a PSU, are there any easy ways to reduce or get rid of it?

 

I suspect (could be wrong though) that EMI from my PSU causes a high pitched buzz in my headphones, but only when playing some games and only on certain screens of games - the operator and weapon selection screen of COD Vanguard for instance. It was fine while I had a TX650M, I only noticed it after upgrading the PSU (upgraded due to GPU upgrade and was at the upper power threshold for my system).

 

I have an MSI MPG A850GF, I've added some ferrite chokes to the audio cables, they helped a bit. I've also found there's certain cable routes that decrease the buzz, but nothing gets rid of it fully.

The headphones are plugged into the audio jack of the motherboard the MSI PSU is powering?

 

[frozensun]

I'm suprised electronics engineer did not make up some component in serial/paralel with coils to reduce vibration.

A lot of guys complaining on this how their graphics card is "crying".

I am actually suprised how some mentioned they even got RMA.

I don't think that should bd covered with RMA since it's normal how coil works.

It is like you buy new Mercedes and complain how its engine is too loud and want RMA.

[rtyall]

17 hours ago, jonnyGURU said:

The headphones are plugged into the audio jack of the motherboard the MSI PSU is powering?

 

It's a PCIE sound card, but yep, getting power from the PSU connected to the motherboard. Currently plugged into the jack in the case panel as that has less buzz than plugging directly into the card, perhaps from the choke on the cable.

[Guest]

9 hours ago, rtyall said:

It's a PCIE sound card, but yep, getting power from the PSU connected to the motherboard. Currently plugged into the jack in the case panel as that has less buzz than plugging directly into the card, perhaps from the choke on the cable.

You should start a new thread about it.

 

[rtyall]

On 8/16/2022 at 7:29 PM, jonnyGURU said:

You should start a new thread about it.

 

OK, thanks. It's not a big issue, just wondered if there was a simple solution. I can live with it, I'm sure when I get upgrade to some higher impedance/lower sensitivity headphones, or get a new PSU or soundcard, it'll be gone.

[RollyShed]

On 8/14/2022 at 1:07 PM, Guest said:

Why does my PC shock me?

If your mains are not grounded, there will be 3.5mA of power looking for a ground. When you touch a metal part of the PC, you become that ground. It’s perfectly safe, and normal, but you really should use a grounded outlet. 

 

Power supplies use “Y” capacitors connected from the neutral to ground as part of their integral EMI filter. These specially rated capacitors provide a low impedance path to the ground for high frequency noise to reduce EMI.

 

3.5 mA - wrong. There is voltage build up and it is feeding current through your body. The amount isn't specific. You do not become a ground unless you are also connected to something which is earthed. You could hold on to 10,000 volts and not feel it if you were sufficiently dangling above ground (in mid air).

 

Y capacitors - wrong. There will be two capacitors, one connected to phase and one connected to neutral and both with their other ends connected to earth which if you are getting a shock is because earth isn't grounded. If you want a letter to describe the connection it would be a "V". The capacitors can be made in one case or be two totally separate capacitors. They are often two separate capacitors.

 

Capacitors conduct AC. Resistors conduct DC.

[Mrderps5974]

I'm new to this forms thing but it's about power supplys I'm trying to buy costume cables off cable mod I have a n rm750e witch they don't say it's supported but they do supporte the rm850e would a cable kit for that also be fine for me?

[--SID--]

6 hours ago, Mrderps5974 said:

I'm new to this forms thing but it's about power supplys I'm trying to buy costume cables off cable mod I have a n rm750e witch they don't say it's supported but they do supporte the rm850e would a cable kit for that also be fine for me?

All RMe use the same cables like 95% of the current Corsair PSUs do.

[Vishera]

On 8/29/2022 at 1:44 PM, Dean0919 said:

Hmm, what happened? Why OP's name & status says just "Guest"?

JonnyGURU had an altercation with another forum user and rage quit the forums.

I won't say who, but i am probably one of the few people who know about it.

[armen2]

On 8/14/2022 at 5:37 AM, Guest said:

Why does my PSU smell like it’s burning?

 

It`s normal for new Transformers to release some harmless odors from the varnish impregnation used in the coils for a week or two after energization. Older Transformers can also release some odor if loaded to a higher level than they have experienced previously in their history.

I just found this Vishera over " Common Issues/Questions" 

[TechSage.]

I have a question about power supplies, specifically if a 650 watt psu will be sufficient for an rtx 3060 ti , a triple fan rgb radiator and an i5 12600k.

 

(not sure if it matters as much as the gpu but my motherboard is the Msi Z690- A Wifi DDR4)