More actions
| EliteBook 850 G5 Freezes when lifted or pressure on bottom | |
|---|---|
| Device | EliteBook 850 G5 |
| Affects part(s) | Back plate |
| Needs equipment | Phillips Head Screwdriver, Electrical Tape |
| Difficulty | ◉◌◌◌ Easy |
| Type | General |
Problem description
When the laptop is lifted, sitting on an uneven surface, or slight pressure is applied to the back the laptop will either freeze or have a serious kernel error.
Symptoms
- Screen freezes and user cannot proceed without power cycling the system
- Windows blue screen error message stuck at 0%
- Screen is half black in a checkerboard pattern
Solution
The bare metal back plate comes into contact with the RAM modules when pressure is applied to the center of the back of the laptop. I added a bit of electrical tape to insulate the metal from the RAM. Combining this with Elitebook 850 G5 Not turning on, 3.2 boot error I have been able to use two modules of RAM without crashes.
Additionally, I found that flexing the RAM sticks towards the board crashes as well. I added a small dab of hot glue on the middle of the stick to prevent it from bending toward the motherboard.
Diagnostic Steps
Gently press on the edge of a RAM stick while the system is on to see if a crash occurs. If so, add a bit of hot glue to prevent the case flexing the RAM module.
Repair Steps
When the coating of the back plate is scratched, the conductive metal is exposed. I measured a resistance of 0.3 ohms between two scratched points. Additionally, when plugged in to the wall, I measured some amount of 60 Hz AC voltages around the back plate. Adding any insulation will help increase this resistance and I believe there is enough clearance for a small strip of electrical tape.
- Remove the 10 screws from the back plate. They are captive screws so they stay on the back plate and don't come out.
- Set your finger tips into the grove of the hinge on the back of the laptop. Slowly pry the plate back. There are multiple loud clips holding it in place so don't be afraid to use a bit of force.
- Place 2 strips of electrical tape on the back plate where the RAM makes contact. See the picture for location.
- Align the back panel with the hinge placement. Using your palms, press the panel into the back of the laptop by applying pressure around the edges. You will hear several loud snaps as the clips set in place.
- Screw the 10 captive screws back in place.