DV7 Turns on, 1 sec then off, CPU fan turning

July 17, 2011 at 07:17:46
Specs: Windows 7, AMD Turon II UDC M600/2.4GHz
DV7 Turns on for about a second, then shuts off, with/without battery connected/not connected to AC, can hear CPU fan spin up. Opened, cleaned, reseated CPU heatsink with arctic silver, fan spins freely, still no-go, unlooked HDD, CDRom, WiFi card, nogo, pulled RAM, comes up with bad ram beeps that are interrupted by the shutdown. At this point I can replace battery, CPU, fan/heatsink assmb, all somewhat of an investment, any been on this trip yet?

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#1
July 17, 2011 at 08:03:35
Apparently your Pavilion model is a laptop.

Have you, or is it possible anyone else who has access to this laptop have
- dropped it, or dropped anything on it, or subjected it to a physical jolt otherwise ?
- spilled liquid on it, or exposed it to liquid such as rain, or sprayed it with liquid ?

Has this laptop been exposed to a power failure event, and/or a power spike or power surge, or have there been lightning strikes in your area, when the AC adapter was plugged in, since the computer last worked properly ?

Any of those things can damage the laptop such that you must replace the mboard or other components inside the case.
.......

The internal fan must be connected to the correct header on the mboard, and it must be able to spin at at least the minimum rpm of the range of rpms the bios's code expects.
If it's connected to the wrong header (not likely on a laptop), or if the fan can no longer spin that minimum rpm, the bios will auto shut off the mboard within a very short time.
If there's nothing else wrong, if the laptop has been used a lot, the fan may not be able to spin at it's minimum speed the bios expects anymore - replacing the fan may cure your problem.
......

The main battery can develop internal shorts inside of it, the older it is the more likely that is, and that can cause all sorts of problems, but you say it still "shuts off, with/without battery connected/...".
.....

The mboard was probably supplied to HP by a mboard maker, and was not made by HP.

Some mboards develop this problem - electrolytic capacitors were installed on them that were not properly made, and they fail eventually - the mboard manufacturer didn't know they were improperly made at the time the mboard was made.

Open up your case and examine the mboard to see if you have bad capacitors, and/or other findable signs of mboard damage .

What to look for, mboard symptoms, example pictures:
http://www.badcaps.net/pages.php?vid=5
Home page that site
- what the problem is caused by
- he says there are STILL bad capacitors on more recent mboards.
http://www.badcaps.net/

Pictures of blown capacitors, other components, power supplies, fried Athlon cpus, etc.:
http://www.halfdone.com/Personal/Jo...


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#2
July 18, 2011 at 06:36:53
Sits on desk, no spills, drops, or any of the above, may have actually been used on battery once, otherwise plugged into the same UPS as a desktop computer, which is still fine. As freely as the cooling fan spins, can't it being the problem unless yellow pulse wire not giving signal or mobo net seeing it. Is there a key-combo that causes system to ignore prelim POST faults?

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#3
July 18, 2011 at 20:07:54
Did your examine the mboard to see if it has one or more failing capacitors?

"Sits on desk, no spills, drops, or any of the above, may have actually been used on battery once, otherwise plugged into the same UPS as a desktop computer, which is still fine."

The major reason for buying a laptop computer rather than a desktop computer is it's portability - it can be used on the battery alone. If you don't actually need it to be portable then you always get more bang for your buck when you buy a desktop computer. Laptops are relatively fragile in comparison to desktop computers,.

If anyone else has access to this computer, then it's possible it has been dropped or it has been exposed to liquid without you being told about that, especially if whoever it was would likely be afraid to tell you.

Nothing protects you 100% from the damage caused by a lightning strike.

Whether something is damaged can be random - e.g. one computer connected to the UPS may be damaged but not the other one.

EVERYTHING that connects to the computers must be connected to something that protects it against damage caused by power spikes and surges, etc. - ALL things that plug into the computer that plug into AC directly or via an AC to DC adapter, AND the cable that connects you to the internet, if the computer connects to the device the internet cable is connected to via a wired network cable connection. . UPSs usually DO NOT have enough places to plug everything in that plugs into the computer.
...

".As freely as the cooling fan spins, can't it being the problem unless yellow pulse wire not giving signal or mobo net seeing it."

It's extremely unlikely that the wire for the rpm sensor on the fan is no longer providing output - Ive never seen myself , and I've never seen that mentioned in posts on the web.

It IS possible the female connector for the fan is not getting a good connection if the laptop has been dropped.

If you have used this laptop a lot, it IS possible the fan can no longer spin at even the minimum speeed the bios expects It's very common for the deterioration of the bearings in the fan to cause that, or for the fan to stop spinning..
....

"Is there a key-combo that causes system to ignore prelim POST faults?"

Not that I've ever seen.

There is sometimes a setting in the bios Setup for it (the POST) to ignore certain errors, such as for a keyboard, but you would have to be able to get into the bios for long enough,
....

You have either a Dv7-3079nr or a Dv7-3079wm

US English model
HP Pavilion dv7-3079wm Entertainment Notebook PC
http://h10025.www1.hp.com/ewfrf/wc/...

Canada English model
HP Pavilion dv7-3079nr Entertainment Notebook PC
http://h10025.www1.hp.com/ewfrf/wc/...


Solve a problem
Start-up / Shutdown
Start-up / Boot-up
http://h10025.www1.hp.com/ewfrf/wc/...

Manuals for HP Pavilion dv7-3079nr Entertainment Notebook PC
http://h10025.www1.hp.com/ewfrf/wc/...

No Owner's or User's manual listed

HP Pavilion dv7 Entertainment PC
Maintenance and Service Guide
http://h10032.www1.hp.com/ctg/Manua...

(Bios) Setup Utility
User's Guide
http://h10032.www1.hp.com/ctg/Manua...

Windows 7
Pointing Devices and Keyboard
User Guide
http://h10032.www1.hp.com/ctg/Manua...

Includes
Hot Keys info.

Notebook Tour
User Guide
http://h10032.www1.hp.com/ctg/Manua...

Includes
Lights - what the leds indicate

Does your model have the fingerprint reader option ?
..........


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