MSI P45 Neo (MS-7519 v1.0) doesn't boot Windows after upgrading from Core 2 Duo E4500 to Core 2 Quad Q9400

[tecnocamop1158a02dd]

Hello everyone.


I have an MSI P45 Neo (MS-7519) version 1.0 motherboard.
My hardware:
Motherboard: MSI P45 Neo (MS-7519) ver. 1.0 (Yes, pretty old board but i don't have anything else)

• Old CPU: Intel Core 2 Duo E4500
• New CPU: Intel Core 2 Quad Q9400 (SLB6B)
• PSU: FSP ATX-350PNR
• RAM: DDR2-800
• The system worked perfectly with the Core 2 Duo E4500.
• After installing the Core 2 Quad Q9400 I started having serious problems.
• Symptoms:
• The PC POSTs successfully.
• I can enter BIOS without any problems.

• CPU temperature is normal (around 40°C in BIOS).
• Windows Memory Diagnostic starts and runs.
• However, Windows never boots. As soon as the Windows logo appears, the PC immediately restarts.
• Safe Mode also causes an instant reboot.

I also noticed something strange:
With the Q9400 installed, BIOS reports the CPU running at 2.0 GHz (333 × 6) instead of the normal 2.66 GHz (333 × 8).

• Things I've already tried:

Cleared CMOS.
Reseated the CPU.
Cleaned the CPU contact pads with 96% isopropyl alcohol.
Applied new thermal paste.
Tested with only one RAM stick.
CPU temperatures are normal.
Windows Memory Diagnostic starts successfully.
The old Core 2 Duo E4500 still works normally.
Could this be:
an outdated BIOS that doesn't fully support the Q9400?
a damaged Q9400?
a motherboard compatibility issue?
something else?
Any advice would be greatly appreciated.
Thank you!

 

[citay]

The new CPU definitely needs a more recent BIOS version. Update to the latest one from https://www.msi.com/Motherboard/P45_Neo/support
Shouldn't be a big issue if you can still enter the BIOS, as long as they already had an update function within the BIOS, like M-Flash.

Now, if that doesn't solve it, then it's possible that your old and weak PSU cannot handle the additional demands the new CPU puts on it. You should then try with another modern, decent-quality, known good (borrowed) PSU, and if it works, you can get a new PSU according to my PSU guide. Nothing too cheap, that will only cause problems later. The minimum nowadays is a decent model from a reputable brand, with 80PLUS Bronze. So at the minimum something like a MSI MAG A550BN, or if you want peace and quiet, something like a be quiet! Pure Power 13 M 550W.