GPU Dilemma..any advice welcome.

I wanted to upgrade my GTX1060 6gb so as to play games on max settings with decent frame rates. Decided to go for a 1070ti and got one on eBay for £205. Was happy with that. Guy i bought off contacted me to say whilst he was packaging it he noticed it was in fact a 1080ti. He asked if that was ok and was happy to send it at no extra cost. Was over the moon.

Now the dilemma. I only really need to do 1080p gaming and i used a 75mhz monitor. Is this card going to be overkill and would i be better reselling it at a profit and getting say a brand new RX 5700 XT or GTX 2060 Super. Or would you keep the 1080ti. My specs are below. Would i need to upgrade anything if i did keep it so as not to bottleneck. Would i need more powerful psu?

Any advice appreciated.

Ryzen 5 2600

MSI B350M PRO-VDH

Ballistix Sport 16gb 2400 (4 x 4gb)

ADATA XPG SX8200 Pro 512GB M.2

Crucial MX500 500GB SSD

EVGA White 500W 80+ Bronze

Thermaltake H17 Mid Tower

120mm Arctic Cooling Fan

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