3 Prong AC Adapter crippled my system!

With all the talk of the "3 Prong" adapter, I decided to try my Fiance's 3 prong on my 1530. She has the 600m and the adapter itself is a little more compact than the 2 prong that was sent out with my system. I double checked to make sure the volt. amp. etc... was exactly the same as mine and it was. So I plugged it in an the computer ran normally. The power indicator indicated charging status.

Later that evening I was playing TF2 clocked @ 625/850 and I was lagging big time with only ~20fps. I am usually @ 50-125fps @ default resolution under most circumstances. I reset my card back to default settings @ 475/700 and I was still lagging. I rebooted and tried different servers and the lag never went away.

It then occured to me, the only change I have made to the system that day was plugging in the 3 prong. So in the middle of game play, I unplugged the chord, my fps immediately shot back up and game play was smooth. I plugged in my old 2 prong and the lappy continued smooth with high fps. I plugged the 3 prong back in and the game lag increased, and my fps shot down again.

I am 99% certain the 3 prong is not defective, and as I mentioned earlier, I verified the amps, volts, hz, all that stuff was identical to mine.

What kind of issue is this?

 

I've been using a two year old 3 prong adapter that came with my 1505 on my 1530 since I got it. I have the 3 prong plugged in the living room and the 2 prong that came with the 1530 in my office. I haven't noticed any difference. The 3 prong I have is just as big as the the one that came with the 1530. They are both 90 watt. I have another smaller 3 prong thats only a 65 watt and I do notice that the 1530 doesn't charge very fast if it's plugged in to that one.