Irregular bluescreen effects.
Irregular bluescreen effects.
In short, my cousin sister received a refurbished HP Elitebook 840G (Intel 8th gen) for college, but it kept showing bluescreens from the beginning. Now I have the laptop with me to try fixing it locally. The issue is random BSODs with the message "Whea uncorrectable error." A quick search suggests it might be a software or hardware problem, but nothing concrete. I noticed it crashes when connecting to Wi-Fi and browsing the internet, then randomly stops afterward. It doesn’t crash during boot in BIOS, which makes it tricky. My sister attempted a Windows reinstall, which failed during installation and caused a crash. She mentioned trying a safe mode, but that didn’t help much. I see dual-channel memory—Hynix on one side and Samsung on the other. This mix-up might be causing trouble. The memory changed recently for troubleshooting, but timing checks are hard because it crashes before any hardware tests. I’m considering disabling many BIOS settings to see if that prevents the crashes. I’d like advice on what to adjust or disable and whether it’s worth a shot. Thanks for any guidance!
WHEA refers to a hardware problem involving the CPU or a PCIe component. On laptops, things can get confusing because the firmware sometimes behaves oddly, but it still points to an error. It’s not always clear if the issue is hardware-related compared to a standard desktop built from standard parts. If you managed to install Windows, check the C:\Windows\Minidump folder for any dumps. If you find them, move the Minidump files back into the Downloads folder (use your desktop if needed). Compress the folder and send it in an email. Follow the instructions carefully—Windows doesn’t allow changes in certain directories.
If no dumps exist but Windows was installed, consider the NVMe SSD as a likely culprit. Examine the crash arguments to identify the exact error. If the system freezes during the BSOD and you can’t retrieve dumps, skip that step. However, if it restarts after a few seconds, adjust the settings on the guide page by disabling automatic reboot.
To modify the BSOD display, edit the registry at HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\CrashControl. Create a new DWORD value named "DisplayParameters" and set its value to 1 (use hex or decimal). Save and reboot. The next BSOD should show these values in the top-left corner. If the first argument is 0x0000000000000010, it indicates an NVMe SSD issue—take a photo of that number if applicable. This adjustment only works for WHEA_Uncorrectable_Error BSODs.
I collected a few new memory dumps. Some turned out empty while others contained information.
Only a few files were readable since others were damaged (you can notice the 0b size). All intact files indicate a CPU problem. Specifically, an internal timer malfunction in the processor appears to be the cause. As mentioned earlier, laptops often face these issues due to BIOS or driver problems, so we should start there first. A defective CPU is the primary concern. Corrupted dump records aren’t typical for CPU faults either, but the timestamps suggest repeated crashes shortly after one another. This might point to a crash occurring while creating the dump file. The creation happens during the next startup, so frequent BSODs during updates could explain the pattern. Updating the BIOS carries risks—malfunctioning during the process may permanently damage the motherboard. At least consider updating the Chipset driver, which is software-based (Management Engine, Chipset Installation, Dynamic Platform and Thermal Framework). Decide whether a BIOS update is safe based on your warranty status. If applicable, reach out to the seller to see if they’d like you attempt the update. Before doing so, clean the CPU thoroughly—don’t know how well it was refurbished, whether only the exterior was touched or internal work was done. Ideally, also replace the CPU cooler if thermal issues are suspected.
The actual variable remains unclear. The system doesn’t crash in BIOS, though it did when Windows installed, suggesting a software issue. I’m unsure if dump files point to the same problem. Both memory references match exactly. A BIOS update might be an option since it works in BIOS but won’t fix deeper issues. If the BIOS is outdated, the system likely won’t function properly. You might need a chipset driver update, which I plan to try. I’m sharing what I know to give you more insight. The second method you mentioned could help.
If the system fails during Windows installation, the CPU might be damaged. You can attempt reapplying the cooler and ensure it's free of debris. All collected dump files indicated the same problem. I use WinDBG Preview to examine the logs, but troubleshooting WHEA crashes requires more expertise since you need to consult the Intel Programming Manual to interpret the final four bytes from the lower MCi in the dumps.
Consider removing the Wi-Fi card if it's modular. It seems the system frequently encounters BSODs when trying to link to the internet. The Windows setup likely struggles to set up network adapters, and tools like CPU-Z attempt to connect during startup to verify updates.