You don't get any starting equipment at all - just the gold
The "Starting Equipment" section at the start of Chapter 5: Equipment states (PHB, p. 143):
When you create your character, you receive equipment based on a combination of your class and background. Alternatively, you can start with a number of gold pieces based on your class and spend them on items from the lists in this chapter. See the Starting Wealth by Class table to determine how much gold you have to spend.
So by the rules, if you choose to buy your equipment, you don't get any equipment from your class or background. Ask your DM, however, since many houserule different starting equipment, especially above level 1.