PS3 (slim) sometimes doesn't boot (Partial GLOD?)

I have a second hand PS3 Slim (CECH-2501A) that I recently bought, and while I was using it, it suddenly stopped outputting video, I turned it off and reset the video and plugged in an AV cable and nothing, when I turn it on, it shows a green light but no video or any other response, even if I try to boot to safe mode by holding the power button, it only turns it on, and then off again after about 20 seconds, it doesn't even give the second beep of resetting video when it's in that state.

Firstly I thought the HDD was the culprit, so I've tried swapping HDDs with a brand new one I have and nothing, it gives the same problem, I even tried turning it on without any HDD and the same problem happens.

But one thing that is weird is if I unplug the PS3 and hold the power button to remove all energy in the system, then plug it in and turn it on, it boots normally with or without the HDD (obviously without the HDD it gives the "no system found" error). The error seems to come randomly, sometimes it happens and sometimes I can turn the ps3 off and on again 5 times in a row and it boots normally.

So I came here to ask you experienced people, what could be causing this issue and is there a fix or should I complain to the store since I still probably have warranty?

PS: When I went to buy it, they also offered me a model 3XXX but I picked up the 2501 because it had support for CFW, which I never installed, It's on OFW, but could the 2XXX series be more prone to these faults and I get a 3XXX one?