Power Surge damage

[solariz]

About a month back I experienced a power surge as a result of load shedding(scheduled black outs) in South Africa. There was not a black out for my area that evening but the lights dimmed and brightend which i suspect was caused when another area that had a black out had their power restored. My PC restarted as a restarted as a result and worked fine everytime i switced it on. However in the morning when i connected the power and switced on, it would switch off in 5 secs during the POST! This happend a few times and then it finaly did boot into the windows xp splash screen before it switched off abruptlty. The last time i tried switching it on i smelled something burning before it went dead! subsequent tries resulted in only the cpu and case fan coming on with no leds lit up. I cant trace the smell to locate what component blew!My ram,hard drive, gfx card etc work on another system except my cd writer and prescot cpu.the mobo is an ECS 661FX.Any ideas how i can fix the mobo? and is the PSU stil safe to use?

 

[sailer]

The two most likely suspects are the PSU and the motherboard. I would suspect that the OS had been corrupted, except that you list it as being tested in another computer and it worked with the other one. The burning you smelled was probably from a capacitor that had died from the repeated shocks. I'd replace the PSU first, upgrading it if necessary at the same time, and see if the computer turns on. If it still doesn't start, then the motherboard probably died. Since you have an Presscot CPU, this might be a time to install an all new motherboard and CPU. Sometimes a bad capacitor is easy to see, being burned, bulged, or leaking. Other times, especially if its hidden inside the PSU, its bad , but you can't find it.

Frequent blackouts, and brownouts (low power from the electric companies) are a big reason that many people have bought Uninteruptable Power Supplies. These even out the power surges and give you time to shut down the computer before damage is done, or they can power down the computer automatically.

 

[solariz]

Thanks for your reply and advice.The mobo was tested on another PSU using the same CPU but with no luck.I was surprized and fortunate that only my cd writer was destroyed with the mobo and CPU.Someone told me that CPU's are generaly tough so would still be good!Guess not.I am in the process of building a new budget system with the ffg specs E2180 CPU & gigabyte G31-S2L mobo.I've tested the PSU with a multimeter with no load aswel as with the ffg load resistors, 7.5ohm,16ohm,100ohm and 27ohm.The voltages measured with and no loading where 11.65 on all +12V pins, 5.01V on 5V pins,3.31V on 3.3V pins.All of these fall within the 5%tolerances.However the negative rails for the -12V was -10.98V & -4.98V for the -5V.These measurements showed that the PSU did indeed regulate with varying loads on all rails at once and 5V was present on the "power good" line.Short circuit test worked with the Psu switching on a few secs only when the short was removed.Is this how u test if a psu is workin or am i missing somthing?

 

[sailer]

CPUs are actually rather delicate. Electrical impulses can kill them quickly. That's why power surge protectors or a UPS are good to have. Where I live, the electrical current varies so much that without a UPS, my computer would crash a lot.

It looks like your PSU is within spec for the most part, though the 122v line is a bit low and the -12v line is quite low. What you don't know is how much power in amps/watts that is being produced. With the damage that occurred elsewhere, it might be best to have it checked by a shop, or if that costs too much, simply replace it. A PSU is the heart of a computer, for it powers everything else and if it malfunctions, either the computer won't work correctly, or it may be damaged. Since it appears that the CD writer, CPU and motherboard were all damaged, I would figure on replacing the PSU as well, to be on the safe side.

 

[solariz]

Prior to "Load Shedding" being implemented in South Africa I never experienced any power surgers or any other problems since purchasing it in 2004. This was rather surprising since the ECS 661FX was a crappy mobo anyway. From my research into PSU's the +-5V and -12 volt rails are not realy used in modern mobos except to power the RS232 serial interface and some peripherals and therefore is not critical. With respect to negative voltages, the tolerances are usualy much larger than the positive rails. I asked a friend to measure the voltages on his PSU and they corelated quiet close to those of myn and so I decided to take a leap of fate and build my very first system using the old PSU! It took 15 minutes and the exhiliration in building a system that works first time is such an adrenalin rush I can't seem to sleep!!!!! wooohooooooo . Ofcoz the first thing I did check is voltages "measured" in the BIOS where acceptable before booting into windows and will continue to monitor voltage stability both in the BIOS and physicaly via a multimeter . Could you and anyone else reading this thread take measurements of your PSU rails and post them. thank you

 

[sailer]

Just took a quick look at some of the voltage readings. The +3.3v line is at 3.25v, the +5v line is 5.02v, the +12v line is 12.15v. I don't remember the others off hand, but those I have can give a comparison.

Congrats on the build. Glad is was successful. I remember my first build and the anxiety I had when I first powered it up. It worked, and yes, it felt like a time to celebrate.

 

[solariz]

Thanks man.. My PC is still going strong and "watts" more it's Super cool and silent compared to my presscot not to mention Super fast!!!

When did you build your first system and what was its specs if you can recall?

btw did u measure the negative rails?

 

[sailer]

I built my first back in the 1990s. It used an Intel 486SX CPU that ran at 25mhz, which I doubled to 50mhz. It first had a 40mb hard drive, 16k of integrated sound, and 128k of ram I upgraded it with a Turtle Beach sound card, a 1gb hard drive, 128k of video ram and 2mb of ram before the motherboard failed. I moved from there to a Pentium 166mhz machine with a 2gig hard drive that was predicted to be good until the year 2000. That didn't happen. I jumped next to a Pentium II 450mhz machine. In 2000, I turned to AMD and stayed with AMD through four different CPUs and two motherboard designs until a few months ago when I build my present gamer with an Intel QX9650. I've found that by getting top quality hardware in the first place, I can keep a basic build about four years, not including upgrading graphics cards.

I haven't gotten around to measuring the negative rails. Been a bit busy through the day.