Question Upgraded CPU in a Toshiba AIO, and now a mystery...

Jun 13, 2021
Hey everyone, I hope I can get some assistance here. I was given a Toshiba AIO, an LX815-D1210. I was going to pass it on to a friend, but I wanted to do some upgrades first. It's not a bad system but I wanted it to at least be better able to play some of their favorite games. I found a pin-compatible i7 2620M (it comes stock with a Pentium G950), and as it was only thirty or so dollars and the system had been free, I picked that up first before adding any RAM or a new SSD (neither of which I've done).

The i7 was a drop in, and after puzzling out the disassembly of the thing, I got it installed and thermal paste reapplied, no problem.

The issue starts after boot. The computer will run for about ten minutes, then shut off. Not "go through power cycle", or go to sleep, but shut off like you unplugged the power cord. It's the same amount of time, every time. My first thought was that it was a thermal issue, so I installed MSI Afterburner to look at that. Nothing seemed out of the ordinary, ran at about 40' idle. I threw a couple of benchmarks at it, Unigen Heaven was one, and while the temps got up there (close to 60C), it did fine, until it didn't.

I thought that perhaps even if the CPU was pin compatible, there was a wattage issue, the system couldn't provide enough power, maybe. But the i7 is a 35W part as is the Pentium, so the draw should be the same. I dug deep into Intel's data sheets for the chipset, the CPU, and the CPU that it replaced, and they are all listed as 100% compatible. The shutdowns occur if the computer is very active (benchmark running) or sitting idle at the desktop or even login screen. There's nothing abnormal happening vis-a-vis windows' behavior. I've gotten in to the BIOS and left it there, and the behavior is the same. Booted up off of a Knoppix thumb drive, again, same.

Could this be the behavior of a bad CPU? Or what exactly is going on here? Any guesses? I thought perhaps the BIOS might have some kind of "Hey, the CPU's been changed, acknowledge this please" but the BIOS is really locked down. The chipset, by the way, is the Mobile Intel® HM65 Express Chipset (Intel® BD82HM65 PCH). Again, per Intel, the 2620M is supported by this chipset.

I'd like to not have to go back to the slower G950, when the system is running it gets a definite boost with the i7 in there! I hope it's something someone can help me solve, I feel like I'm running in circles here.


Just being chipset compatible may not be the only key when dealing with a 'proprietary' system like that.

Where there other options available with the same system?
IE did Toshiba sell this same model with a Core series processor?
It could be a BIOS thing. It could have to do with the VRM on the motherboard, could even be the power supply.

TDP can be very misleading number to use in regard to actual system draw. An i7 is for sure pulling more than the Pentium G.
I do find it unusual (as well) that you aren't seeing higher temps or a propensity to do so more often under load, if such were the case.