I'm not sure what the 950 will cost in the USA, but I'm certain that the 1060 will only be 100/150ish more. This is the card you should go with IMO instead of a 950, by far. 1060 should outperform a 980, and I ran a 980 recently with AH/beta, and you'll be fine at max or close to it with that. I'm not sure I understand your explanation of your system capabilities, if you're stuck with a PSU you can't use a 1060 or other card that needs connectors, maybe the 950 is your best option.