M17x R3, power supply general question

I have already posted one other question about this laptop, but I figured I’d start a new thread since my other issue was resolved. This particular laptop uses a 240w psu, which at the time I still do not have, as the original owner kept it, one is currently in the mail to me though as I write this. I do have another Dell psu, but it is only 130w.. I know the laptop I bought works, because I was able to test before I bought it. The one time I tried to use the 130w psu, the lights came on, but no screen and no fans, and I got 7 beeps.. which from what I’ve read indicates a bad cpu

Now.. I know it is a good operating unit, and common sense says that happened like that because I am using an underpowered PSU and the laptop did not detect correct voltage. 

I would like to know if I am thinking correctly, or somehow the cpu actually went bad between their house and mine. I am hoping it is just because I’m using the wrong psu initially. I am currently at work, so I won’t be able to be there and test when the new psu shows up for about another 6 hours or so, so I am hoping someone with more knowledge will reply before then so I don’t keep thinking I just broke my new-to-me Alienware