I've been running an ASUS GTX 670 DirectCU II TOP for the past two and a bit years now and I've not had a single problem until this week. While I'm aware the temperatures in the UK are quite high for a change, I wouldn't expect a two year old graphics card that cost nearly £400 to overheat and give me temperature readings like the picture attached below:
That was taken while running Heaven Benchmark and shortly after I tried playing a few games that I usually do, all of which returned temperatures similar or higher. The strange thing is, I've never had temperatures go so high on this card, even during summer last year it peaked at 76c. However this year It's hit 90c+ a few times and actually throttled itself causing my PC to shut down. I'm still under warranty for the card but I've been told that I'm most likely to expect a repair as they don't stuck GTX 670's anymore and even If they did, I'm not currently a fan of ASUS in anyway as I've had a number of problems with them over the past year.
The main thing I use my system for is gaming so I'm looking to future proof myself a little bit as I did previously with the 670. I have a little knowledge about graphics cards but not enough to make the decision over what is a worthy upgrade.