Can I mine bitcoin with a gaming computer? Awhile ago i built a rather nice gaming computer it has
CPU: intel i5 6600k
GPU: Nvidia GTX 1080
Ram: 16 GB ddr4
PSU: corsair Ax1200W
Water cooled system

Would this be a decent mining machine. If so what would you predict its stats to be. What should I upgrade.
It is not profitable to mine Bitcoin with computer(s) and GPU(s). If you just want to help secure the network and/or keep your place warm in a high-tech way, then you could mine Bitcoin ;)

It could be profitable for you to mine some other coin, using your computer and GPU(s). You could also set your computer up to rent its computing power to others by joining services like miningrigrentals.com

For GPU mining have in mind that the more GPUs you have, the better. Since you don't pay the cost of electricity, you might want to add more GPUs to your computer. Just make sure the Power Supply Unit (PSU) can handle them.