Extremely loud, sharp crack!

[steppenwolf]

dont open the power supply either

i suppose a new power supply and check out house wiring should be enough to get off the subject

i cant see how a monitor would make a computer reboot

[janusz]

Eureka! Power Supply!

I decided to take a look inside the PS can. I disconnect the power plug. Then as soon as I began removing the PS I heard something making a rattling sound. I found a piece of loose plastic (?) inside the PS box. I was very, very careful. Minimum contact. I laid it down and got a bright light and large magnifying glass. After examining components I finally found it. The solid piece I found covers about 75% of a hole in a package. I did find smaller pieces.

Last mystery. Help me figure this out. I am wondering what this is that allows the PS to continue working. Is this some protective device gone bad? Visible through the opening: there appears to be a solid connector between two round points with one end blown out. These two points seem to be directly above the inner leads labeled "AC." BTW, the fuse was not blown.

The damaged component has 4 leads. No part number - blown away. The outside leads are labeled + and -. The two inside leads have the label "AC" between the leads.

I mentioned protective devices because this power supply has Built-in Triple Protection: Over Voltage Protection, Over Power Protection, & Short Circuit Protection. I suppose they all do. This one also has thermally controlled fan speed.

Here are the specs on the PS (HPC-300-101/EN-8304946):

http://www.enlight.co.th/PSU300.htm
http://www.highpowersupply.com/product-ps-hpc300101.htm

In this pix it is the dark object just to the right of the cap. It is about 1/2" square, 1/4" thick.
http://computer.howstuffworks.com/power-supply.htm

This pix has a similar layout but lacks this particular component which is located in front of the nearest cap.
http://computer.howstuffworks.com/power-supply1.htm

Sorry I couldn't provide digital pix - all the installed software to extract the images are on THAT machine. :-)

Thanks,

janusz

[SuperSparks]

I'm not 100% clear from those pics what component you're referring to. But from the discription it could be either a bridge rectifier or the Stand By transformer I think. I certainly would advise that you replace the PSU, even though everything does appear to be working.

[Train]

Replacement time for sure. Sounds like a blown connection in that component welded itself instead of burning up.

[alphanumeric]

I agree with SuperSparks, from your description it sounds like a bridge rectifier. Time for a new power supply I'd say.

[janusz]

Well, with the two +/1 and the two AC terminals it appears to be a rectifier module. Sure is small for the power involved. (In the pix it is in front of the cap - black about 1/2" high, a black thingie.) So, I'm probably getting filtered pulsed DC output (half-wave).

Yeah, definitely time for a new PS. I will order tonight. About the only thing I can salvage from the old one is the very quiet fan.

As I think back I suppose the sound bounded off the wall giving me the perception it was at or above the monitor. Man, that was some kinda loud noise. Given the choice between the monitor and the PS, I'll take the PS.

Thanks for all the great comments! It could have been any of the possible causes suggested! I love the roach-fry suggestion.

Have a great week!

janusz

[SuperSparks]

Have a look at this recent thread before buying just any old power supply:

http://discussions.virtualdr.com/sho...hreadid=169836

[janusz]

Thanks kindly for the suggestion.

Antex True430 is my choice.

[We will be in your great city in October -- vacation. Wonderful city and country! I have business in London from time to time plus we visit every couple of years.]

janusz

[kxn]

My PSU also died from a loud pop or crack if you will. But the computer couldn't boot afterward with that PSU (works great with a new one). Not an engineer, but I think the voltage regulator (a three-lead big "transitor" screwed to a big heatsink) blew. I saw a big long crack in it. No smoke or fire.

Oh, the cause was that I forgot to plug in the additional power molex for my Radeon 9500. Probably the PSU was cheap that came included with the case.

[wonderinguy34]

I did a monitor tune-up of the Samsung SyncMaster 950b monitor (color adjustment, etc. using Samsung Natural Color software).

Its possible it was just the monitor reacting to the tune up.
I picked my wife up at work one day and while I was waiting she was straightening up the office and used a duster on the monitor screen to get off the dust,that gives off a pretty good "CRACK" sound especially since the monitor was still on,it also caused the comp to reboot.
Anyway she says the comp never developed any problems,but she never used a duster on the monitor again

[Nix]

Originally posted by wonderinguy34
Its possible it was just the monitor reacting to the tune up.

Did you read the previous posts ?

Specifically

Eureka! Power Supply!

I decided to take a look inside the PS can. I disconnect the power plug. Then as soon as I began removing the PS I heard something making a rattling sound. I found a piece of loose plastic (?) inside the PS box. I was very, very careful. Minimum contact. I laid it down and got a bright light and large magnifying glass. After examining components I finally found it. The solid piece I found covers about 75% of a hole in a package. I did find smaller pieces.

Last mystery. Help me figure this out. I am wondering what this is that allows the PS to continue working. Is this some protective device gone bad? Visible through the opening: there appears to be a solid connector between two round points with one end blown out. These two points seem to be directly above the inner leads labeled "AC." BTW, the fuse was not blown.

The damaged component has 4 leads. No part number - blown away. The outside leads are labeled + and -. The two inside leads have the label "AC" between the leads.

I mentioned protective devices because this power supply has Built-in Triple Protection: Over Voltage Protection, Over Power Protection, & Short Circuit Protection. I suppose they all do. This one also has thermally controlled fan speed.

Here are the specs on the PS (HPC-300-101/EN-8304946):

http://www.enlight.co.th/PSU300.htm
http://www.highpowersupply.com/product-ps-hpc300101.htm

In this pix it is the dark object just to the right of the cap. It is about 1/2" square, 1/4" thick.
http://computer.howstuffworks.com/power-supply.htm

This pix has a similar layout but lacks this particular component which is located in front of the nearest cap.
http://computer.howstuffworks.com/power-supply1.htm

Sorry I couldn't provide digital pix - all the installed software to extract the images are on THAT machine. :-)

Thanks,

janusz