X51-R2, not booting

Hi, I inherited my friends old PC after she considered it broken as it wouldn’t boot into windows. I remedied the problem by mashing f12 on every boot and selecting windows 8.1 rather than windows set up which it is defaulted to. A few months have passed with no issue until 2 days ago, I update the Graphics card drivers, and did a windows update, restarted and my graphics card no longer works, and will not show up in device list, I took the card out and tried it on my test bench and found it to be working fine, so I put it back in and still no joy. I tried re-installing the NVidia drivers but could not install as the card was not found. I then found in a previous post to try flushing the bios, I did so and no change. I then updated windows again and now I can’t even boot to windows. If I force a power down by holding the power button I am able to press f12 to enter the bios, but other than that I simply go to a coloured screen (which normally is where windows starts, but it will go no further and no text is shown) If anyone knows what to do beyond this help would be greatly appreciated. PC Specs: Product name - Alienware X51 R2 CPU - intel core i5-4460 @ 3.2GHz GPU - Nvidia GTX960 Warranty has expired, and unfortunately no recovery disk was set up, I’m hoping that I don’t have to purchase a new windows key just to fix this.