You are building this custom mid-range gaming desktop to lock in smooth frame rates and reliable performance for the next four or five years. Buying solid mid-tier parts now means you avoid the trap of cheap upgrades next year and skip the absurd markup of bleeding-edge hardware.
Timing the winter holiday sales is your best move here. Brands usually drop prices on last year's graphics cards and processors right as the newest models hit the shelves, giving you top-tier performance from six months ago at a steep discount.
That 0% intro window is a strict deadline, not free money. If you still have a remaining balance on the Citi Simplicity® Credit Card when those 18 months are up, deferred interest rules or standard high APRs will kick in fast.