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Computer Power-Up

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by f.ware

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The last 3 computers that have come into my shop have given me the same problem -- no matter what I do, I can not get the system to power up. I have done the following to all 3 systems:

1. Replaced the MB and ALL componets inside (HDD,Optical, FDD, Fans, Cables)
2. I have used different power supplies in each. (450W - 600W)

In each case, I get LED lights on the MB, the fans on the CPU are spinning but nothing else! (No POST, no beeps, nothing) The only thing that I really have not changed is the chassis. (SIDE NOTE - I have changed parts from one chassis to another and updated the BOIS but still the same results.)

In 13 years of IT, this is a first for me. Any advice?

23 replies

by dawgit

...a dumb question but, Have you checked your line voltage, power sorce lately?
On those Power Supplys are they voltage switchable, or auto-switch? Did these power supplies just come from overseas? Personally I would try a new power supply, but if there was a short in one of the mainboards destroying the diaodes in your power supply that might not work either. -d

by f.ware

Yes, I did check the line voltage and power source. That was my first thought and I did switch the power suppolies. To the best of my knowledge, the ps where made in the US. Thanks for the reply.

by dawgit

for the feed-back, and the Thumb too. :D
Have you found the problem yet? I think you have us wondering now. -d

by thechas

Another thing to try is a different power cord. A missing ground, or a poor connection in the power cord can cause some strange symptoms.

It would not hurt to check your bench keyboard and mouse too.

How did you update the BIOS is the system will not POST? I hope you mean that you reset the CMOS.

You mentioned changing the motherboard. What about CPU and RAM?

It might be time to get a POST card so that you can find out what where the POST process hangs.

Chas

by f.ware

We test the units with four different cords. I stripped the unit down to where there is only the chassis, mb, cpu, hdd, and ram and still get the same results. We download the BIOS & new firmware to a fdd and use a intergration software tool that will allow us to customize the BIOS. We have ordered a new POST card as a backup and to make sure that we did not destroy the one we have. Thanks for the advice.

by f.ware

Yep, the power source and electrical main was our starting point. We test them with known good systems and the 3 in question. Thanks for the input.

by oh smeg

As if you got unlucky and have a run on the same problem cropping up at the same time. Unfortunate but it happens.

Have you checked the actual Cases to see if a Switch on the front has been filled with gunk and is sticking? I had a Reset Switch sticking recently and it was a bit hard to find till I pushed it and then realized what was happening.

Col

by boxfiddler Hot topic

at 31.2 Kbps to a complete load of Print/View All. The ONLY way to read these threads without spending an entire night trying to read only 3 or 4 threads.

And you can?t reply until TR has finished loading the page. At least not at this speed. Brings up a 404 Page Not Found every time. (Discovered the hard way ? by repeated attempts and repeated receipts of 404!)

[b][i]Note:[/i][/b] It took longer to add the comment than it did for the page to load.

by f.ware

No, I have not check that.... I will do that and let you know the results. Thanks

by oh smeg

While not common it is a possibility. a long time ago I got 3 Faulty Antec PS's which was very unexpected. Only reason I remembered that one was a order with 100 DVD Blanks on it that where all faulty last week.

Maybe a different model or brand of PS may also be of some assistance here or at the very least a Known Good One to test with to see if the problem persists.

Col

by f.ware

Thanks. I have had this happen before as well and with Antec PS. These PS are Theremaltake and I test each one prior to putting them in the unit. Thanks for the heads up.

by f.ware

No problem with the thumbs, I value any and all that offer help and feel it is the right thing to do if it gets me closer to solving my issue and it's respectful. I read/respond to some of the 'help call' on this forum and don't get a "thanks" or even a "go to hell".

I did get one computer going... I started from scratch and put in new mb binding post and moved to a 580W power supply and PRESTO - it came on. I am going to try this with the other two and see what happens. Wish me luck!

by Former member

Open up the case(s) and hold down the processor around the heatsink (get someone to power on for you), while holding down the processor around the heatsink the computer should kick in. If not take out the processor and give it a good clean then apply a little thermal paste and re-seat it, then put the heatsink back on.
Hope this works for you.

Please post back if you have any more problems or questions.

by f.ware

Good idea! I will give it a try and repost my finding. I have in the past had a few processors that did not have enough thermal paste or didn't have it at all. Totally overlooked that one. Thanks!!!!!

by f.ware

Didn't work.....but is one hell'va clean cpu and mb. :)

by Former member

There might be a shortage somewhere from the motherboard to the case.

Please post back if you have any more problems or questions.

by oh smeg

If the monitor displays the No Connection Message when you plug it into the Video outlet the PS is in the process of dying.

Only seen this once when a customer bought a new M'Board, CPU, RAM and Video Card with no improvement to the computers functioning and when I replaced the PS it sprung to life and has worked perfectly ever since. Didn't matter that the Fan's, LED's and so on worked properly the Not Connected message was what attracted my attention and even though the Power Supply measured OK the current must have been down though the voltages where correct. This only happened when you tried to turn on the system with the main Front Panel Switch any other time it acted like it was working correctly.

Buying a new computer because you have a bad PS still sounds a tad expensive to me though and this guy didn't save himself my fee either. :D

Col

by f.ware

I changed the stand off using new washers and whata' know, we have power! Now I am down to one computer but the owner just contacted me and decided to go with a new custom system. Thanks a million for your advice.

by f.ware

I am really thankful for everyone's helpful input and advice. As I tell my staff, I know a lot but I don't know everything. I do hpe that I can be of assistance to all of you one day in the future. Once again, OUTSTANDING JOB TO YOU ALL!!!!!!!!!

by f.ware

I am really thankful for everyone's helpful input and advice. As I tell my staff, I know a lot but I don't know everything. I do hpe that I can be of assistance to all of you one day in the future.

I tried to give a thumbs-up to Pecoret Tietokoneet but the button would not work so I want to aknowledge his very helpful suggestion of changing the standoff washers.

Once again, OUTSTANDING JOB TO YOU ALL!!!!!!!!!

by Former member

Please post back if you have any more problems or questions.

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