I'm working an HP dv9000 and am having some very weird issues that I can't seem to find the culprit to.
here is what happens
-about 10% of the time the laptop boots perfectly into vista, audio working fine and everything. This usually happens on fresh boots. For example, if the computer is left to sit overnight or a few hours I'll comeback and it'll work fine.
-about 20% of the time the computer boots with "no audio device detected"
-about 70% the computer posts and when it trys to boot into windows I'll either get 1)a blank black screen or 2) a black screen with the MICROSOFT CORPORATION logo at the bottom very dimly. I've let it sit there for about 20 minutes and nothing. So after it does nothing I use the power button to restart the computer because ctrlaltdel does not work. Then it'll ask me whether i want to boot in safe mode and all that good stuff. If i select START WINDOWS NORMALLY it'll successfully boot into windows about 30% of the time and the other times it'll give me one of the black screens described above.
-this is a fresh installation of vista on a new hdd because according to the owner the hp self diagnostics reported a bad hdd. I did a quick tested the HDD with HD TUNE and it passed. HOWEVER, i went ahead with the new hdd because I had seen cases on other acer laptop where the disk would show healthy smart status and pass hd tune but for some reason I couldn't boot into the OS CD unless i took out the hdd or replaced it with another.
- I also had a hard time having the pc allowing me to boot from the dvd drive. The bios recognized the dvd drive but it wouldn't boot from it no matter what i did. So i switched the Vista DVD for a 7 CD and pressed f9 to select boot device and there it was. After this, i simply switched 7 for Vista again and selected the DVD Drive as a boot device and it worked.
What i've tried so far:
1-put the old HDD back in and see what happens. Once the new hdd starts giving the blank screen, if i put the old one in, it'll do the same.
2-i've tried switching the hdd from slot two to slot one(this particular hp machine has two hdd slots. If i put it in slot one the machine simply reboots and never posts.
3-I've ran memtest and RAM passed. I've tried running with one stick, one stick on another slot, and a completely different stick.
4-I've tried doing all the windows updates up to sp2. I've installed all drivers on HP website including the audio but somehow i can't get the audio to ever work consistenly.
5-I've flashed the latest bios, a middle date bios and the original bios and none of them show any improvement.
6-Thinking it was the maybe the DVD drive that for some reason causing an issue, I tried booting without the DVD drive and with a new DVD drive and nothing happened. It made no difference.
I'm baffled by this computer!!! I have no clue what to do with it. I've tried everything I could think of. Please help!
I used a universal laptop ac cable and set the voltage to 19.5 (1 volt higher than the 18.5 the hp is rated at) and the laptop works perfectly!! I've successfully booted 5 times now. HOWEVER, the blue ac light on the laptop is not turning on anymore. Could the increase in voltage have damaged the led in the ac port?
Also, could a 1v increase in voltage damage the laptop? I've never had to do anything like this nor have i ever seen anything like this....
The blue led on the ac jack now turns on again....
my windows time and date have been reset to 2007!!
Audio still not working.
gong to attempt to reinstall audio drivers again as well and change date and time and see if any more updates are available.
currently on stock ac adaptor.
Sounds like the board is wacked... As it heats and cools and gets bounced arround micro cracks appear in the solder points causing breaks and shorts. Depending on the temp or the surface the computer is on it acts differently as some cracks are pushed closed or spread wider.
I have a feeling this laptop will become one of those things that will never be figured out.
I got the feeling that it was just what bucknutty described, your best bet at a repair is getting a replacement mobo from HP or ebay. Make sure you can take it apart and get it back together though before going that route. Otherwise, just dismantle it and sell the RAM, CPU, HDD, LCD, DVD Drive, etc (trash the mobo though). Alternatively, sell it as a broken unit for somebody else to part out or repair.