Do you intend to replace certain parts and put this thing together yourself???
Or have a shop do it?
Or buy another entirely new PC pre-assembled and ready to go.
You could generally do quite well for 900 assuming you bought certain parts and put it all together.
I know little about video cards so that may blow up your budget. But 900 for motherboard, CPU, new RAM, new power supply should be fine at 900 or maybe less. You might be able to keep existing DDR 4 RAM. Maybe even power supply? Figure maybe 200 to 250 for motherboard and 250 to 400 for CPU? Maybe 125 for 32 GB of new DDR 5 if thought necessary. Decent power supplies might begin around 100?
I don't game.
I think that video card was introduced last year near 400 or 500 euros and can use up to 250 watts.
I assume this is primarily a gaming machine, so video cards can really eat up a budget. For all I know, spending 900 on a new video card will gain you more than replacing all the other parts for 900.
Let someone else comment on how much of your 900 should be spent on a new video card.......IF ANY?