Chosen Solution

I have an HP Pavilion laptop, a 2012 Model # dv6-7013cl, approximately 6 years old, and out of warranty since 2014. When turned on, the caps lock flashes continuously - no blink code - and the F12 orange button light stays on. It will not boot or show anything on the screen. The laptop previously worked without issues other than overheating easily. For this reason, I disassembled it and cleaned the fan. There was a layer of lint inside the fan housing so thick that I at first thought it was a foam filter strip. After removing the lint and cleaning off dust with brushes and ear swabs, I reassembled everything and found the laptop in its current no-boot state. The fan runs and blows warm air, and at a much better rate since being cleaned. The computer will power on with only the battery, with only the power cord, or both, and the screen flashes for a fraction of a second before going back to dead black and beginning to flash the caps lock light. I have since disassembled and reassembled the laptop at least four times and left it charging overnight without any change in its condition. I’ve quadruple-checked for missed connectors, board damage, etc. and found none. NOTES: (1) Because the CMOS battery is fit tightly into the laptop’s plastic frame, I had to disconnect it in order to remove the motherboard and the fan for cleaning. Thus the BIOS was reset on an old battery. (2) I initially misseated the memory cards, but found this problem and fixed it before the second reassembly. Reseating the memory cards multiple times has not changed the problem. I used photos prior to disassembly to ensure that they were replaced in their original slots. (3) I have read through and followed all relevant sections of the HP Support Document “Computer Does Not Start and Emits an LED or Beep Code” found at https://support.hp.com/ph-en/document/c0…. The caps lock key is NOT blinking a code; it is blinking continuously at a rate of about 1 blink per second. Besides reseating the memory cards, I’ve tried the “Hard Reset” described in the HP Support Document. I’ve also tried the ever harder reset described here on IFixIt: Caps Lock and Num Lock LEDs blink continuously, can’t get to BIOS I am seeking diagnostic and repair suggestions from people with ideas. I appreciate all help and will follow and report back on any suggestions that are provided. Thank you!

I would say it is very possible the system overheated and burnt up the gpu before the system cleaning.

I have had overheating issues with my Pavilion DV7-3010so from 2010 for about two years, the fan was running continuously at high speed. I bought a cooling stand which improved the situation somewhat. You may may wonder why I spend money on such an old PC instead of buying a new one. There are a few reasons: the PC is otherwise in good shape, it has two drive bays currently containing two 2TB drives which few new PCs can hold, I prefer Win 7 and finally because I like the tinkering. I disassembled the PC and found the cooling paste had dried which I wasn’t even aware could happen. Three ICs were cooled by the fan assembly: the middle one had a silicon pad and the outer two used paste. So I cleaned up all three and applied Kryonaut to them. After this, the chips ran at a temp about 10C lower and the fan kicked in sparingly. I decided to try a CPU upgrade from AMD Athlon M300 to Turion II M540. I also bought a sheet of silicon pads. When I disassembled the PC again I found there had been good thermal contact (i e the paste had spread well) for the outer ICs but not the middle one. I cleaned them again, replaced the CPU, put a pad on the middle IC, paste on the other two and reassembled the PC. When starting up there was no fan noise which made me wonder if I had reassembled everything correctly. However, when i shone a light onto the fan I could see that it was starting and stopping in short, low-speed bursts while making very little noise. Even when I run Furmark the temps no longer reach very high levels and the fan is fairly quiet: of course. the faster it spins the more it will contribute to running down the battery. The CPU component of the experience index has jumped from 4.9 to 5.9. Overall, I’m pleased with both the improved cooling and the extra performance. I’m a little sceptical about the concept of “frying” a CPU or GPU. That may have been valid long ago but nowadays with various temperature sensors automatically monitored by the chipsets the risk should be small. Of course, it’s always possible for sensors to stop working …