PS3 sometimes launch and sometimes don't

Question

Somebody gave me a PS3, and when I power it on, (From no light to red light) it stays on. Then, after I push the power again, the light changes to green and I can hear the disk start to spin, and then power goes off completely. But here's where it gets odd: Sometimes it stays on for 3 seconds, sometimes I can play for an hour or so, and sometimes it gets as far as the PS3 intro screen and then shuts off.

Also, when I first got it (from a friend), it had a game stuck in it and I had to open it up to remove the game. Right after I took out the game, it worked fine for about an hour. If this helps, I have the 3001a series with no disk light.

Answer 1

Although I never faced such issue, I think that,

1) Electric:
Is your electric stable? Get a stabilizer and try again, as your electric might cause this.

2) Dust:
It might be dusty, try to open it (it'll opt you out of warranty system [do you call it "warranty void?"], but in this case, you already opened it, so it should be no problem for you.) and clean it, heat caused by dust can crash it/slow it down.

3) Heat:
Try to start it in a cold place.

Answer 2

I had the exact same problem with my PS3 a couple of weeks ago. The first thing you want to do is to rid it of dust. Completely clean it. If you have a handheld vacuum, it will make the process much faster. This in itself should allow yourself to play your PS3 for a week at least!

If not then it could be a power problem. Never switch off your PS3 by flicking the main electricity switch. Make sure to switch off the PS3, wait for it to turn red then flick the main switch.

Alternatively, this video works for people for the original PS3 (not the super slim one) You may have to get your hands dirty for this one:

If you do however tamper with it, the people at Sony may not deem it as their problem since there is evidence of possible tampering. You choice.

Putting a ice pack after playing is also an easy way to cool your PS3 down.