It doesn't hurt to have more PSU than you need as you will have lower load percentage and have more room for degeradtion. All PSUs loose some capacity each year, but higher quality parts degrade less. The difference between a 750 and 850 shouldn't matter in terms of watts for a single card build, which has not been overclocked beyond what it comes with from the factory, unless running a 3090 with extreme power limit and one of the intel CPUs that will boost to 250w (that combo can use 700+ watts for a minute or so in extreme cases on factory OC). If you feel the difference in price is negligible then go for it and have some extra capacity for the future, otherwise save your money for something else. This is assuming the PSUs are of equal quality build wise.Working on new build. Was going i7 10700k but decided to do Ryzen 5 5600x instead because of the single core performance (photoshop) and less heat. Just a simple 1080p build:
Ryzen 5 5600x with Arctic Cooling Esports 34 Duo
Msi B550 Mortar WiFi
16 Gb DDR 4 3200 (or 3600)
2 SSD or 1 m.2 and 1 SSD
6 120mm Case Fans
Will be using old MSI Twin Frozr 7850 2Gb OC until video card prices stabilize. 750 watts is probably overkill but I could get the same Seasonic in 850 Plus Gold for just a bit more in case I get a power hungry graphics card later but really can’t see me getting any card that needs more than 750.