Problem after undervolting

So i undervolted following flipfire's guide. (Thx! nice guide)
I found my stable voltage for each multipliers and and ran stress test using Orthos for good 1~2hours each.Didnt get any BSOD.
So i assumed it was a success and did a test run.
The one thing i noticed was that, for some reason,the frame rate while playing TF2 increased (30~60fps) and i was surprised that it was actually playable.
Before undervolting, my fps for TF2 was 14~30fps, it was barely playable with that framerate with default recommended video setting.
i thought undervolting does not effect any performance at all.

Now the bad thing:
when playing TF2 my GPU/CPU gets really hot eversince undervolting it.
It goes upto 98C and cpu going 80C thus causing my system to shutdown.
It keeps shut down for every 15~20min for getting hot while playing the game. It wasn't like that before undervolting, the temp would stay under 80C but get lower fps as mentioned above.
So i closed the RMclock at start up and tested again, the gpu temp stays firm below 80C playing TF2 but with low fps.

i know i followed the guide right but it keeps doing that eversince i undervolted it.
My laptop setting is under my sig.
Did i just overclock my cpu??
How did undervolting increased the fps rate in TF2?