Precision T3600 Power supply questions

have recently aquired a precision t3600 workstation, about 8 years old and everything seems to be running fine.

I want to put a Geforce GTX 1080 Graphics card in it, others have had success and no problems at all, i intend to use this workstation for gaming.

I want to know if it will be safe to put in? the power supply is aging and i'm somewhat worried that if it gives up it might bring the 1080 and any other hardware down with it.

the computer itself doesn't make any weird noises, it runs fine.

its also not like you can just go out and buy a new replacement unit either...

any suggestions?