Preventing DEAD motherboards!

[TechGuru78]

I've been a PC technician for 10+ years now. I am thoroughly fed up with experiencing DEAD motherboards! Despite all the efforts to prevent ESD (electrostatic discharge) and large amounts of money invested in high-quality power supplies/etc., I still run into motherboards which stop working for no apparent reason. I've tried countless combinations of memory modules, video cards, etc. The problem still persists: the motherboard fails to do anything. The onboard fan power still supplies power to the CPU fan, and the power supply works perfectly, but no power to the power LED, no speaker beeps,... nothing. There HAS to be more knowledge on this issue. At $100+/motherboard, I'm going bankrupt. All help will be appreciated, but please... no run-of-the-mill replies like "check the cables", "wear an anti-static wrist band", etc. I need advanced help with this. Thanks.

 

[jc14all]

Without much detail pertaining to your hardware brand and setup I can only generalize.

1. CPU not seated properly.
2. M/B trace grounded by case stand-off.
3. Clear BIOS jumper jumpered to clear CMOS instead of normal.
4. BIOS flash crash, causing Boot Lock.
5. Bend or shorted pins on jumpers or cables.
6. Scratches across a trace on the M/B or cracks in the M/B.
7. Faulty power supply.
8. Incorrect type DRAM (pin mismatch).
9. ESD.
10. Human error.

I'm sure there may be something that I have forgotten, but you provide the details and we will try to help.

JC-------<*){{{>{~~~~~
Fisher of men

 

[Guest]

If they work for a while, then die it may well be a heat problem. Normally a fault like accidental short to case, or damage due to ESD will be immediate. (I think ESD is the most overused excuse for failures... Seems like anytime a tech is perplexed, he yells ESD and pats himself on the back for a fabulous find.. BAH!)

I did notice that some HS fans require more current than the MoBo traces are able to supply (for example, ThermalTake web site warns not to hook up a 7000RPM fan to the MoBo, but rather use an adapter and supply it from a P/S feed)

So, my suggestion is get some air moving in those cases. I think it is the #1 preventative measure.

 

[jc14all]

One most overlooked problem I forgot to mention, which should be the first thing to do; is check the power outlet with an inexpensive tester. Making sure you have no opens/hot ground reverse/hot neutral reverse. Faulty wiring could be a probability not not always likely.

JC-------<*){{{>{~~~~~
Fisher of men

 

[TechGuru78]

Here's the system configuration:
FIC FA-11 VBA42NR motherboard with FC-PGA socket 370.
256 MB. PC100 SDRAM.
10 GB. IDE hard drive.
Internal Iomega Zip-100 IDE drive.
SB Live! PCI card.
Creative Voodoo Banshee PCI card.
Intel Pentium III CPU at its normal 866 MHz. (133 FSB * 6.5)
Enermax 330 watt high-quality power supply.
Full-tower Black Dragon case with 5 cooling fans (COLD!).

Here's what happened:
I installed the motherboard, parts, etc. into my new Black Dragon full-tower case which I bought because my old cheap ATX power supply's fan crapped out. System initially booted OK, but kept losing BIOS settings in CMOS. Found out it was a switch that got moved during assembly; fixed. Next boot, Windows ME loaded just fine. After the initial startup apps finished loading, I put a Zip disk into the Zip drive. When the Zip drive powered on, BAM... the system froze completely. After powering down and turning the system back on after about 15 seconds, the motherboard was dead.

One possible cause is that the power outlet used had no ground; it had a ground connector, but has no ground wiring (thanks to my slumlord) -- which caused anything connected to the ground to hold a constant current (enough to numb your entire arm). I tried an outlet tested to be properly wired, but the motherboard still fails to respond. The power supply is brand new, as well as the case.

Something like this happened in the past, when I pushed a floppy drive into the 3.5" bay while the system was powered on. Yeah, kinda dumb idea, but I don't understand why the motherboard would go dead.

Thanks for all your replies. Any further technical info would be greatly appreciated.


HUGE savings on name-brand clothing and merchandise at http://www.denasresaleshop.com/

 

[jc14all]

______________________________________________________________________________________________

<b><font color=blue>"One possible cause is that the power outlet used had no ground; it had a ground connector, but has no ground wiring (thanks to my slumlord) -- which caused anything connected to the ground to hold a constant current (enough to numb your entire arm). I tried an outlet tested to be properly wired, but the motherboard still fails to respond. The power supply is brand new, as well as the case."</b></font color=blue>

______________________________________________________________________________________________

Do you think possible a voltage surge/spike could have killed you power supply? Does it smell burnt? It sounds like you need a UPS, instead of a power stripe to protect your investment (PC). Recommend that you try another/different power supply to confirm that the one you are using isn't the problem. I wouldn't trust the outlet power without a UPS.


JC-------<*){{{>{~~~~~
Fisher of men

 

[jc14all]

Just curious, did you find your problem?

JC-------<*){{{>{~~~~~
Fisher of men

 

[zwaarst]

sometimes when you power on electric machinerie or you do the plug in the power poit you see a bleu flash. This is beceause the electromechnetic field resists to a change of flux. When you connect things when your computer is on the same thing can happen. power peaks of 100 Volt can appear. As you can imaging your computer is not made for that and some parts can die. The same thing happens when you turn on your computer, only the power suply is made to prevent the large power peaks with all kind of electronic things. But sometimes they fale. That is why it is best to let your computer on. Most computers die by powering on.

somebody correct me if i am wrong

<font color=red>duk-tape is like the force, it has a bright side and a dark side, and it keeps the universe together.</font color=red>

 

[TechGuru78]

You're somewhat right...
It's kinda like a car... if you know you're going to go a few places, go in a single trip, instead of making seperate trips. The same goes for computers... if you know you're going to use your computer later in the day, it's better to leave it on. A few reasons: less wear-and-tear on the hard drive, less stress on the circuits (cooling down and then heating up stresses components), and no waiting for the boot-up process.

Whatever you decide to do, the motherboard shouldn't fail because of either way.

Power supplies are designed to regulate power and are actually better surge protectors than your average store-bought ones. Simply powering on the system, even if a slight surge exists, shouldn't fry the motherboard. However, a direct lightning hit surge can, as I've experience in the past.


HUGE savings on name-brand clothing and merchandise at http://www.denasresaleshop.com/

 

[Guest]

One of the biggest killers of MBs has been power surges. It also is one of the biggest causes of PC lock-up. Spikes cause voltage blips in the wrong place @the wrong time. These get reflected all over the system. Best solution I have found is to use a UPS. A second issue is PS is too small for the load. You get nasty spikes when you power-up even with a UPS. I deal with PS spiking regularly in my engineering job. You would be surprised @how $$ are lost in manufacturing for this issue.

Basic Rules:

1) Use a UPS!!!!!!!!
2) Oversize the PS
3) Don't do hot swaps
4) Don't move socketed HW while powered up
5) Make sure you have your house supply grounded

Been there & paid for it.......