Fixing an Old dv6000 with No Video (In North Vancouver)
This HP Pavilion entertainment laptop was from a lady living in Vancouver downtown. On Nov 17, 2010, I met her and her boyfriend at the entrance of her apartment of 42 floors high. It was raining and they were just returning from airport with luggage. They invited me to go up to their apartment and she went to several rooms to find the laptop for me. She finally pulled it out from a box in the guest room right at the entrance where I was waiting. She had the laptop only. AC adapter, laptop battery and hard drive were missing.
While I was riding bus home, I inspected the laptop. It had scratches on the top cover most likely due to other stuffs inside the box when moving around. At the bottom, the COA label missed the middle portion. Fortunately, the full Windows Vista Home Premium product key was still on the remaining part to activate the OS.
I had an AC adapter from previous HP laptop that had broken wires. I soldered the wires and added a plastic cover to protect the wires. The AC adapter matched with the laptop. At boot up, the lights were on but no video. My testing instinct was telling me that it had the GPU overheat problem. I opened up the laptop to the fan compartment. This was the first time that I saw the vent was completed clogged with dust. No wonder that the GPU was overheated and disconnected from the motherboard.
I did a slow reflow on the GPU to re-establish the connection and re-applied the silver thermal compound to both GPU and CPU. After reassembling the laptop and booting it up, the video was back. I put in a 120GB Hitachi used hard drive with an HP recovery partition to the lapotp. At boot up, I pressed F11 to restore the HP laptop to factory image with the laptop. When the Windows Vista Home Premium was started up, I tested WiFi and Youtube video. It was stable for a month. On 15Dec2010, I bought copper sheets with 1.2 mm, 1 mm, 0.5 mm from a metal store to test the effect. I tested the 1.2 mm first that was thicker than the gap to put pressure on the GPU. However, the effect was opposite. The copper contact with GPU should be off that the GPU got overheated and having the no video again.
I did the reflow again on 16Dec2010 and put in a 1 mm copper shim to fill in the gap in exact thickness. However, the wireless was not working. Since reflow failed, I ordered a tested Navidia GPU which came with balls. When I removed the GPU, the circuit underneath was pilled off and damaged. On 4Aug2011, I got another motherboard with GPU failure from a young man. He provided the case together. He told me that after reflow, I should let the solder cool down slowly. I followed his suggestion to re-flow again on 5Aug2011 and swapped the case. On 3Sep2011, although it was not used much, the wireless blue light disappeared, start up was extremely slow but video was still working. The reflow failed again in a month even I cooled it slowly.
On 8Sep2011, I did the reflow again with soldering paste, higher temperature, heating up and cooling down slowly. The wireless blue light was back again. I had been checking it for over a month that the reflow was stable before posting it for sale. It was picked up by a student in North Vancouver. Knowing that it was for student, I provided $20 discount.
After almost a year in shelter, this laptop was able to serve again on 3 Nov 2011.