That should really be one of the first things you check when GPU temps don't seem right, it is for me at least. You probably don't even need compressed air to clean it, with those types of coolers you can usually just remove the fans with a couple screws and brush of the layer of dust that builds up on top of the heatsink with a soft paintbrush.
If it's just going to be used for cleaning computers you should be ok with a small 2hp 20litre compressor for around £100/$130. One thing I do recommend though is making sure you get a moisture trap as it's not a nice feeling when you go to clean out your PC and end up spraying water all over it (I speak from experience).
You can use something like HWmonitor and alt-tab after playing for a while to check the temps or you can use something like MSI Afterburner + Rivatuner and have an in-game overlay.
First of it's keyboard not key broad I have never personally seen a keyboard that need's 'unlocking' (probably before my time), but I found this forum thread that may help you out:
http://www.sharkyforums.com/showthread.php?118668-Unlock-Keyboard-(old-skool-computer-question)
Well then to me it sounds like there is either something wrong with the CPU header or the pump is damaged is some way, although it is strange that the pump starts working after 17 minutes as you say.
I would try a different header on the motherboard and check the BIOS settings just to be sure, if that doesn't work I would maybe look at getting one of those 3/4 pin-to-molex adapters as they are very cheap and see if that fixes your problem. Failing that, I would contact Corsair and see if I could RMA the cooler, IIRC they come with a 5 year warranty.
Where have you connected the pump to? Maybe its not set to come on until something reaches a certain temperature, a bios setting perhaps. In my case I have a 4-pin to molex adapter that I have connected the pump to, this ensures that as soon the computer turns on the pump will turn on instantly and run at full speed.
Maybe you have it connected to a chassis fan connector that is only set to turn on when the temperature reaches X amount.
Cool, I just thought it was a strange amount of RAM to have, you usually see like 32, 64, 128GB, still a multiple of 8 though so probably not that unusual, I don't deal with servers very often