1. overall impact on my pc in the long term
This entirely depends on the GPU and how long your mining per day. If your mining on it full time you should do some maintenance every month or two replacing thermal paste and making sure fans are clean. If your on a water cooled rig the maintenance is less as you do not have fans moving contently at max speed.
2. How many hows a day it requires to actually break even on power usage
This again massively varies on the card and the rest of your components and environment. If the rest of your components draw large power it will be harder to break even or profit, If your in a country with high electrical bills again it makes it hard, If your in a hot country your fans will work harder in your case. There is a lot of variables.
I basically noted my avrg power bill over 3 months not mining after this I mined for 2 months. I looked at the difference between those bills and how much I made from the coin and that gave me my answer as to profitability. Not a 100% accurate methodology but close enough.
3. is it really making you money in the long run?
Again it depends on the above factors if you bought a GPU specifically to mine it would take 4-8 months to pay the GPU off after power.
As I didn't buy the cards just to mine I do not look at the cost of the cards, as I would have bought them without mining anyway. I also tend to upgrade my render P.C. around every 3 years so I am not to worried about the card having issues before i would replace it. The Plex server I do not know when ill swap out the G card in as its not really necessary Plex does not need great hardware so that card may get overwhelmed or get to the point where its not worth mining on as new technology's come out because the profits from that older card decrease.
Sorry I cant give you 100% accurate answers but hope the above helps a little.
Cheers,
Stefan
