Is my graphics card failing?

Hey all, I have a P25w. When gaming the GPU regularly gets to 80c and the CPU to 93c (idle GPU ~40s and CPU ~50s). The computer usually sits closed on a laptop cooler in a mildly warm room with a 24" monitor plugged in.

For a few weeks, I've experienced the following problem: periodically, the monitor will go blank and display the "signal lost" message. Simultaneously, the laptop's fans will rev up. This will last for just a second or two before the image comes back up and the fans slow back down. Additionally, immediately after exiting a game the monitor and fans will cycle in this manner every ten or fifteen seconds for several minutes. The problem will usually persist through a reboot of the computer.

This happens both at idle and while gaming, although while gaming the fans are obviously already at max. Initially, this occurred only a few times a day. Lately it seems to happen much more frequently.

I performed a clean reinstall of both the latest Intel and latest Nvidia drivers recently which did not fix the problem. The same problem was exhibited on the previous version of the Nvidia drivers.

To me, this sounds like a failing GPU. HOWEVER, I also suspect the Nvidia Optimus software because the GPU never seems to have gotten hot enough to damage itself. Before I involve the Gigabyte warranty process, however, I'd like a second opinion on that. What do you think?

 

Update: I've troubleshooted some and found two things.

First, the lid seems to keep a lot of heat in when it's closed. I tried using the computer with the lid open and noticed that the idle temps were significantly lower (almost 10c!) and the gaming temps for the CPU were peaking in the upper 80s rather than the lower 90s. So, keep that lid open, at least a little! The GPU peak temps were not significantly affected by the lid being open or closed, but its idle temps were.

Second, when the lid was open I was not using my external monitor and the screen off/on issue did not happen. This implies that it's either an issue with the cable (I tried two but they were both pretty old), the port, or the monitor. I'll update when I learn more.