XPS 15 9550 - PCH Diode overheating

Question

Hello,

I own a 2 year old XPS 15 9550 with full HD display (no touch screen).

The laptop is connected to a DELL TB16 with two 1080p monitors (and other peripherals such as mouse, keyboard, headphones etc.)

I repasted the CPU & GPU and added pads to the MOSFETS.

The CPU & GPU are undervolted and I'm running throttlestop.

The laptop sits on top of a running cooling pad at almost all times.

All of the laptop's hardware runs cool but the PCH Diode doesn't.

*All the numbers below are according to AIDA64.

When idle, most parts run at <50 degrees celsius (some at around 50), while the PCH Diode runs at around 70 degrees.

When loaded (games, CAD etc.), most parts run at around 55 degrees celsius, while the PCH Diode runs at around 95 degrees.

Most of the times, when loaded, the cpu throttles down from around 2.6 GHz to around 0.8 GHz, which makes using the computer frustrating.

Most of the time, the fans are running wild and make a lot of noise.

*The PCH Diode's temperature is high even when not plugged to the docking station but only to the original 240W power adapter (not enough tests were made when using only the battery).

I have tried installing the latest drivers (including the BIOS update) to not help.

Can someone please help me figure out how to fix this?

Update: According to recent tests I performed, when idle and running on battery alone, the PCH Diode is running at around 55 degrees celsius.

samos1111 · Answer

> Most of the time, the fans are running wild and make a lot of noise.

Sadly they can't cool the relevant area - almost zero airflow there. You might be able to take the heat to the nearby fan housing rather than to the backplate.

samos1111 · Answer

Try double-checking temperatures using HWinfo64.

High PCH temperature might be caused by overheating of a voltage regulator located nearby, near the battery connector. It was seen on 9560 FLIR thermal images at Notebookreview forum. Perhaps you could try padding it to the backplate?

Mind high temperatures sure ain't good for battery health. I recall someone reported high temperatures there in relation to battery replacement. Any correlation with battery charging (indicated by the white LED)?

omerwass1993 · Answer

Thank you for the response, I tried padding the diode as you suggested but that didn't help. As an update, the PCH Diode is cooling rapidly to around 55 deg. celsius when running on battery alone on idle, according to more recent tests that I performed.

XPS

XPS 15 9550 - PCH Diode overheating

Was this post helpful?