hello
I'm working as pc tech and I'd like to have an answer to a specific issue.
It happened to me several times and I don't know how to handle this.either I have to do with desktop or laptop,there is one common symptom. Black screen,fan spins for a while,and after that pc turns off.
the things I test are:
1) ram and ram slots
2) bios battery
3) gpu
4) cpu
5) even wifi cards
In the end I tell clients that "it's another dead mobo" and I give them back their pc.
Assuming that it is surely something that has to do with mobo.what causes this issue?I mean is it the power circuit?capacitors?something else?
My regards
Hi! Do you not test the power supply??? Do you clean the dust from the PC. The things you list are good but IMHO not near enough to say it's the MB.
There are some very cheap meters to test power supply. How To Fix a Computer That Won't Turn On
forgot to mention the psu test with multimeter as far as the dc jack...and the path to the mobo
ok I'm quite new to the field.these are my first steps,this is why I asked for advices.
for example post test card is something that I had no idea about it. (thank you)
may dust cause such problems;
That just means that the power to the PSU is OK....doesn't mean that the power leaving the PSU is OK. The PSU could have a bad power line on one of the rails or any other line (leads). The only sure way to veryfy is to pull the PSU and install a known working one.
[Note: any good tech will have a PSU just for testing]
I've seen this time and time again over the years where the assumed fault was the mobo or CPU and the actual culprit was the PSU.
Laptops - well that's another matter and as Rich M points out....HDD's are usually the culprit.
Dust can cause over heating. which could shut the computer down!!
Allheart55 has a repair shop and can give you some good advise!!
You are very welcome!
It doesn't have to do with one single pc.it's happened several times.
for example I have a laptop in front of me.tried everething.(what I told you + steps according to the article you mentioned) but still nothing.
turns on-fan spins-and pc turns off after a while
I ordered post test card but still try to figure out what exactly is happening
Hi ocer! I'm not replying on threads at this moment. Laptops can be very difficult to fix as the hardware can be difficult to get to. Lap tops are carried around and badly abused. They are getting tougher with SSD's but other parts are still vulnerable to abuse.
I'm bowing out of your thread. I'm sure you will get suggestions from other TSF members. I'm sure you will get more confident repairing PC's with time and experience.
Good luck!
I think part of the problem is you are assuming there is one issue here and there could be many things causing this type of behavior. Psu does come to mind but not likley on a laptop. Hsf loose from the cpu is another possibility. Everything except the actual shutdown points to hard drive that is bad or with issues but a hard drive issue could cause shut down if the drive is really in distress. A clogged hsf could also cause this though again actual shutdown from that is unlikely but a short where a dvd-rw has a really bad issue could stop a bootup or simply a loose wire shorting on the case somewhere or standoffs not used on a desktop to keep motherboard off the case.
In cases where there is a black screen and then shut off, the first thing you check is the power. On laptops the culprit is usually the battery being dead or something wrong with the AC adapter or plugs.
Next thing to check is if it goes to the bios screen. Since you never get to that point, the PC/laptop has a failure to post problem. This is caused by a number of reasons. Sometimes people install hardware that are not compatible to their machine or some piece of hardware fails.
This part gets complicated because every one of the components cause cause the MB to shut down.
The number one reason is usually the CPU. After a while the thermal paste on CPUs are dried up or the fan is faulty so the CPU overheats and shuts down. Usually though there is at least an attempt to post on the PC/laptop before that happens.
Sometimes the problems are multiple, combined with video problems that make it seem like it is not posting. I think you'll find as you fix more and more of them you'll understand what the problems are instinctively.
As the people have said above, the easiest things to do are to do swapping of known working components to eliminate the possibilities. However sometimes that is hard to do on laptops where you don't have extra parts available.
Status
Not open for further replies.
You have insufficient privileges to reply here.
Related Threads
?
?
?
?
?
Tech Support Forum
4.7M posts
957.9K members
Since 2002
A forum community dedicated to tech experts and enthusiasts. Come join the discussion about articles, computer security, Mac, Microsoft, Linux, hardware, networking, gaming, reviews, accessories, and more!