Alienware M14x R1 gaming lags when connected to adapter

Ok, this is really weird. I have had my Alienware M14x for 11 months and it was always running smoothly without a hitch.

my spec:
-M14x R1
-i7-2670QM @2.20Ghz
-Windows 7, 64 bit
-1.5 GT555M GPU
-A08 Bios version
- 8 GB RAM
-1366 x 768 display

It all started when I had just finished installing BF3 and started to play, I noticed some lagging, which was weird because I've played tons of other high graphic games like crysis 2 and MW3 without any lagging at all. At first I thought it was the game so I tried reinstalling it and it still wouldn't run smoothly. After that I tried to play Crysis 2 and MW3 and they were lagging also. I've searched other forums and so far I haven't found a clue as to why this is happening.

Over the last month my alienware had been becoming more and more slow, so I had reformatted my HDD and reinstalled windows 7. Everything was running very smoothly, so I tried installing Battlefield 2 (not BF3) and played it for a while and everything was still lagging like crazy. Fortunately I forgot to bring my charger one time and I tried playing BF2 and it was running very smoothly without a problem, so I tried playing but with the charger plugged in and it suddenly lags again.

So basically:
- Not plugged in = runs smoothly
- Plugged in with battery being charged = Lags like crazy
- Plugged in while battery is full = Lags like crazy

I know that it's supposed to be the other way around and it baffles me, so I checked the settings on my Alien Fusion - High Performance. All of the settings were exactly the same. So now I don't know what to do and I need some help. Does anyone have any ideas?

(Sorry if there's some misspelled words english isn't my native language)

 

Check that your games are set up like this on the nVidia control panel.

 

That is really weird, do you remember updating something from a windows driver to anything etc..? Maybe system restore can fix it

 

What if when you are plugged in, the turbo mode kicks in thus increasing heat hence leading to throttling.

Check your temps when gaming ...

I have an R1 with similar issues, hitting 98c and throttling my games. I am currently on the road to hell, trying to get this fixed.

 

Could be right, have you checked your temps?

Alienware Laptops: How to deal with overheating

 

Even before I reinstalled windows the games were lagging, so there's no need for me to restore and I haven't downloaded any new drivers. I have downloaded the intel graphics driver and the nvidia driver. Now I am screwing around with the nvidia settings.

I dont know if the turbo kicks in or not, just by playing BF2 the temprature can hit over 90c easily. but when I'm not gaming the temp stays around 60ish. Now I'm thinking of selling my laptop and buy a desktop instead, but alienware is so awesome that I don't know what to do.

I just started to tweak the settings, and I hope that there's no more lag