HP Pavilion dv5z-1200 wont start, blinking LEDs

[Al2]

Leds keep blinking once every 4-5 seconds, computer won't even boot into BIOS.  Out of warranty.  The table says the CPU is not functional.  After doing the hard reset several times, after wiping the CMOS, I reseated teh memory modules to no avail.  I have opened the darned thing, reseated the CPU, cleaned the existing thermal paste and replaced with a high thermal conductivity one, and cleaned the lousy thermal gel pads that supposedly provide cooling to the GPU.  All this for nothing.  

Should I assume by now that the CPU is fried, or is there a remote chance that the BIOS EPROM chip is toast and causing all this?  Anyone has any experience in this direction, is the blinking pattern that good at pinpointing the failing component?  Any Jan 11-12 HP Expert  willing to offer their advice?  I have replaced a BIOS chip in another HP Pavilion just last spring, so that wouldn't be a problem.  Just don't want to invest all the effort--and dough--for nothing.  

In any case, this is/was my last HP laptop computer ever.  Between a ze4547 and this dv5z, I have had so many hardware issues, that I'd rather buy cheap netbooks every other year than spend a zillion on expensive, shiny, flashy things with abject engineering inside.   

Thanks in advance to any taker!

[ekigren]

I have dv5-1021 with same kind of problems. Heating cpu socket and north bridge area did bring it up again but only for a day, it also changed blinking pattern to bios corrupt error, still booting sometimes, so bios is OK.

My guess is that north bride or south bridge or cpu socket soldering has gone pad.

[Al2]

THis is real bad news... The conspiracy theorist in me was hoping for some evil planned obsolescence built into the Bios that it just dies after so many power cycles.  I could live with that.  But from what I'm hearing, this is a major design or quality control flaw.  There are so many folks complaining about DV machines not booting or running 20-30 degrees hotter than chip specs.  Imagine the masses who couldn't figure out how to reach this forum!  No decent engineer will ever go forward with releasing improperly tested designs to production and still sleep well at night.  On the other hand I'm pretty sure the greedy manager(s) pressing for so many designs a year or else has no issues whatsoever.  Venting steam...

Okay, I'll train my heat gun on the socket and try a bios chip replacement in this order and will report back... 

[Knute]

Before you start soldering circuits and such, have you checked the warranty?

http://www13.itrc.hp.com/service/ewarranty/warrantyResults.do?admit=109447627+1286541891570+28353475

[ekigren]

Okay, but you might begin with north bridge. I just got my dv5 up and running again by heating the NB. I heated it underside of the motherboard with heat gun and same time from top side (chip side) with gas soldering pen (don't no English term).

Good luck.

[Al2]

@ekigren, this i awesome, i got a bios screen following your advice.  lets see how long it lasts...  i have a bios chip on the way but i wont be using it.  now im holding the display half up w left hand, will see if --and for how long-- it works w/ covers on...  thanks!!!

[Al2]

Well... the repair lasted one week precisely after which the computer crashed midway through a HULU video, and again wouldn't reboot.  Same blinking error code (1).  I reapplied ekigren's fix above and revived it again. More precisely, I heated the AMD Radeon and Southbridge chips, front and back, as well as the back of the CPU slot, using a heat gun set on medium .  I have also started putting lots of holes through the bottom cover of the laptop in the hope that the slightly better cooling will prevent the bad soldering from acting up again.  Will keep posting updates as events occur just so others know what to expect if choosing to repair themselves.

Al

[Al2]

This time the "fix" lasted only 5 days before the original symptom returned (i.e., no boot, black screen, caps lock/scroll lock LEDs blinking once every ~5 sec).  I did manage to narrow the defect down to the ATI Radeon GPU chip.  Over teh past 5 days I had noticed a hot spot somewhere underneath the center of the function button rown of the keboard.  Then, I noticed that heating the back of the CPU socked alone did not fix the defect, but then separately heatig the GPU (top, heat gun on medium) did fix my problem once more.  

This time I went for a solution I have read about on the net a couple of weeks ago:  I removed the thermal gel pad that's supposed to help cool the GPU into the heat sink.  I replaced it with a one-penny coin that I polished carefully onboth sides, cut to dimension, and coated with Arctic Silver 5 thermal compound on both sides.  The general thinking was that one metal layer (zinc in this case) plus two silver compound layers ought to conduct heat better than the stupid 1-mm thick white gel which by now was probably acting as an insulator instead of thermal conductor.  

On top of all this, I have traced the entire heat sink with holes in the bottom cover as closely as possible to improve ventilation.

Fingers crossed and let's see how long this lasts before I have to open the stupid thing again and heat gun the GPU!  I'll keep reporting back with any developments... Heat management in this machine is extremely, extremely bad and this struggle to get things cooling right needs to be documented!  

 

[Nckhammond]

motherboards are about $130 on ebay.. ive replaced about 6 of them. I have tried the copper shim, but the ones they are selling online are a little too thick. (the work great on the dv9000 series thou). i usually put the dv5 heat sink in a vice and bend the part were it should touch the gpu down a 1/16 of an inch or so. when i replace the motherboard then use a high quality thermal paste.

as a side note the dv6 intel heat sinks and the dv5 -1000 series both have the same physical dimensions, but the dv6 ones are much much cheaper made. the dv5's are casted better and the fan has more fins.  going to research this more later, i have only had to replace one dv6 motherboard so far.

[Al2]

Some may not believe this, but I was just on my way to report 3 weeks of trouble-free operation from my ailing dv5, when the **bleep** thing simply refused to wake up from the sleep mode, showing the same symptoms as above.  

I don't know how to unset the green "solved" flag on this thread.  Although Ekigren was very helpful sharing his mostly temporary fix (thank you again!), there is no way in hell this problem is "solved".  

I have paid $700 on a machine I had expected to give me many years of trouble free operation.  It wasn't the cheapest out there, and where I live money doesn't grow on trees either!  What I got in return was two years of many hardware related annoyances, from a malfunctioning brightness control, to the volume control going mad and jumping up and down at will, to horrendeous slowdowns and locks and IDE errors in a system based on SATA technology.  

Turns out this machine, like many other DV's, is designed so badly that chips routinely overheat until soldering eventually fails.  Someone was recommending replacing the main board.  Do I have any guarrantee the replacement board isn't just as crappy?  

No, the solution is not bending my back forward trying to find fixes for something which is unfixable.  For all I'm concerned, HP totally lost the trust of what used to be a recurring customer.  And judging by the number of unhappy posters on this forum, they are losing the trust of many others.  Yes, making shiny, Mac'y laptops may have increased sales on the short term.  But on the long term, it may take one generation before people will forget the beautiful, useless door stops and will start trusting this brand again.