Question CPU Power Limit Throttles at .79ghz, I'm at the end of my wits, pls help!!

Apr 6, 2020
HI everyone,
how y'all doing? I hope everyone is safe and sound in such a dreadful time.
Me, for the past 2 weeks I've been searching the whole internet for solutions to the cpu problem i'm facing, and I've tried everything, this might be my last attempt at solving it, so fingers crossed!!

Here's some info about my laptop:
SONY Vaio Duo 13,
Windows 10 Pro,
intel core i7-4500u @1.8ghz, TDP 15W,
256G SSD, 8G RAM

About 2 weeks ago, while I was browsing the internet, my laptop suddenly froze and the fan started to spin super fast, when everything went back to "normal" about a minute later, i noticed my laptop was running super slow, rebooted, didn't fix it. I didn't realize it's gonna become "permanent" since...
After some checks i realize it's my cpu stuck at .79ghz constantly, no matter what I do, stress tests are pointless because it just won't exceed .79ghz, and the temperature is never high, always around 40°C.

What I've found and tried so far:
  1. It's Power Limit Throttling, as indicated in Throttlestop and intel XTU. (See screenshots)
  2. The Package TDP remains constantly high as 27-31W, even when the laptop is in idle and doing nothing, this greatly exceeds the power limit of the cpu, thus results in the constant PL1 throttling. (See screenshots)
  3. The temperature is always low so the fan doesn't even turn on. (See screenshots)
  4. It happens regardless of whether the laptop is running on battery or plugged in the wall.
  5. All power management setting is set to high and 100% cpu performance with battery savers disabled.
  6. The long and short turbo boost power limits are already set as high as it gets, I also tried undervolting -0.05V, but no matter what I changed or tweaked in Throttlestop and intel XTU, didn't fix anything.
  7. I clean installed win 10, didn't fix anything, might do it again later but I suspect it'd make a difference.
  8. All drivers, windows updates and bios are up to date, and I haven't installed any software yet save Throttlestop, cpu-z and intel XTU.
  9. I don't have DPTF or anything like that installed in the system. Triple checked it.
  10. I didn't change anything in the system or installed anything before this first happened.
  11. I did Memory test, Cpu test, system scan, malware scan, disk scan - all passed, nothing wrong was found.
  12. The Bios for this laptop is very very simple, it doesn't provide any power settings, and I've reset it to default multiple times.
  13. It's a sealed laptop, I can't open it up to take the battery out. But as far as I can see, the battery charges and works just as normal. I also don't see anything wrong with the AC Adapter although I can't test it myself. Nor can I test the temperature sensor on the motherboard.
  14. After my laptop resumes from sleep now, it runs extremely low at .1ghz, virtually unusable, this may or may not be related to the same power issue.
So now, WHAT is causing the constant high package TDP of around 30W that overly exceeds the cpu's power limits, even when nothing major is running?Is it really the directly reason why it's throttling? Could it be caused by some hardware problems? If so, what??

I've literally tried everything from the internet, my case seems so rare that when i googled "high package TDP" there's not even much discussion...
Now I'm at the end of my wits here, i don't wanna have to buy a new laptop right now because this one worked so well before this, it'd be a shame to let it go for some weird unknown problem, and i need to get to the bottom of this even if i do eventually have to buy a new one.

Any thoughts and inputs will be appreciated, and I'll be glad to provide any further information needed, thank you so much!!

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