Dv7-1135nr cpu failure?

Question

I am having a problem with my hp pavilion dv7-1135nr with Windows 7 64 bit. I'll start from the point that it started having issues.
My wife had been telling me that he laptop had been overheating for some time, but I attributed it to the fact that she usually was using it while lying across the bed with the fan smothered in blanket. Then it got to the point that it would shut down all of a sudden. We discussed ways to counteract the overheating (never thought to take it apart and clean the fan and cooling vents though). Then the battery began to not hold a charge and she could only use the laptop if it was plugged in. Then that became unpredictable - sometimes it would turn on, sometimes not. Then it got to where the laptop wouldn't turn on at all, but the charge indicator light would be lit with the charger plugged in. Then one day, no charge indicator light, so I tested the charger and it was fried. I bought a new charger and battery. I charged the laptop, but when I turned it on...
- Power up
- All standard LED indicators light up
- Screen stays blank
- Fan blows for 3 seconds and DVD drive is accessed
- Silent for the next 10 seconds or so until the fan starts up again and CAPS and NUM LOCK lights blink 3 times simultaneously, then don't blink for 2 seconds, then blink 3 times again and this continues...
I tried rebooting, tried to enter bios on startup, I tried fn + f4, fn + f5, Windows logo, etc., but to no avail.
I researched possible problems and solutions online and concluded that the issue was a fried motherboard. I bought a refurbished replacement and after I installed it - nothing changed! Same as before.
I realize that the refurbished motherboard could be defective, but I started researching things related to a bad cpu (after all, it had been overheating for awhile and when I switched out motherboards, the cooling vents were packed full of dust). I stumbled upon a very similar issue on your support forum - http://h30434.www3.hp.com/t5/forums/mobileforumtopicpage/board-id/Hardware/thread-id/56653 - but the posts never concluded with a solution.
I tried what was suggested by the provost Erico:
"Chances are that you have a dead system board. CPUs just don't die very often.
Have you tried a hard reset?
Remove the battery and unplug the DC power adapter.
press and hold the power button for more than fifteen seconds.
plug in the DC power adapter (leave the battery out for now)
press the power button
Best regards,
erico"
This didn't solve the problem. So I tried something else that was suggested by erico:
"Yours is one of the rare notebooks that have an easily removable CMOS battery.
Check the Service & Maintenence guide (page 63) for istructions on removing it. It is worthwhile doing this to reset/clear CMOS before doing anything else. Remove it and all other power sources, press the power button for a few seconds. replace the CMOS battery (or leave it out) and use the power adapter to see if the beast will boot up."
That didn't work either. I tested the CMOS battery and it's good. I checked the hard drive on my pc, it's good. So, it seems that the only possible problems are:
CPU
RAM
Motherboard
LCD display
So, that's where I am right now. I'm leaning towards the problem being a fried CPU, but I'm afraid to spend more $ on something that might not be the issue. What do you think the problem is? What are your suggestions for diagnosing the problem? Thanks for your time and effort on this.
Forever grateful,
Jeremy

Answer 1

Hi there @chiarcher
Welcome to the HP Support Forums! It is a great place to find the help you need, both from other users, HP experts and other support personnel.
I understand that your computer is no longer starting and you are seeing a repeating pattern of flashing LEDs. I am happy to help with this.
As it happens your computer is telling you what is wrong with it.  HP Notebook PCs - Computer does not start and the LEDs blink or the computer beeps
From that page you will find a table including: LEDs blink 3 times         Memory       Module error not functional
The same page includes some things to try to test. It could be one or both memory modules, or the slots on the board that are the problem.
Let me know how it goes, just read though the section on the memory error and see if you can isolate it.
Malygris1
I work on behalf of HP
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