lets see. the one thing missing is your power supply specs.
it looks like your gpu is a hd5770. a nice one for what you are using it for, but can't be too demanding on your power supply. it looks like it is rated at 110 watts and requires one 6 pin PCIe power connection.
also, the 5770 may need to be taken out and inspected for dust build-up on the heat sink where the fan blows air through. if air can't move freely across the heatsink, heat builds up rapidly. speccy is sensing it at 49c, which can be considered above average. if the 5770 is getting a little too warm, it could cause the display freezing and hyperactive fan speed that you describe, so this may be a hardware topic.
it looks like your other temperatures are nothing to cause alarm.
one more thing, did this behavior start after a win7 update install? it looks like the installs have been quite busy in the last two weeks, and the 5770 drivers are from a few years back.
it is kind of common for the win7 auto-updates to hose up or even over-ride a display driver, so it is also common to install/update graphics card drivers regularly. i will link up to the 5000 series card driver host in case you do have the 5750 instead of the 5770. your report just says 5700 series.
Edited by synergy513, 30 August 2014 - 02:25 PM.