Following coverage of the thermal issues that are affecting an unknown cross-section of NVIDIA GPUs (latest here), several readers have been asking me what temperature their GPUs should be in order for them to be safe from any potential problems. Unfortunately, it's hard to give a definitive answer.
It's pretty easy to find out the temperature of your GPU, for example you can use nTune to keep an eye on your GPUs temperature. As well as monitoring and logging, it'll also give you an idea if things are getting too hot, and allow you to take steps to cool things down a little by adjusting the fan.
But ... GPU temperature measurements are spot readings and as such it is possible that you're not getting the full picture. It's still possible for hot spots to develop within the GPU unnoticed. Remember, it only takes a tiny hot spot in the right place to kill a piece of silicon. These hot spots can form for a number of reasons - poor application of thermal grease, inadequate application of thermal pads, other problem with the cooling system, etc, etc etc - and can form very quickly.
Another problem here is that it is unclear why the NVIDIA GPUs are failing, although it seems clear that it is related somehow to heat. It is possible that the GPUs are failing while still operating within (or close to) operating parameters. The fact that the BIOS updates from Dell and HP seem to turn the cooling fan on permanently seems to suggest that there's no safe operating temperature.
So, how cool should your GPU be? Well, the best answer I can give is that it should be as cool as possible without driving yourself nuts with fans roaring away flat out all the time. Normally systems do a good job of controlling the temperature automatically but if you're gaming then there's nothing wrong with kicking the fan up a few notches to help keep the GPU cool. At the same time make sure that the system has adequate airflow and that intakes/exhausts aren't obstructed by anything (clothing, dust ...). That's the best that you can do.
Personally, I'd use the notebook normally, let if fail in the warranty period and get it fixed properly (if outside the warranty period then I'd probably offload it on eBay and upgrade). My personal feeling is that the older mobile G84s and G86s are ticking timebombs and that the same might be true for the G92, and that makes them a liability I can do without.