Replacing your computer would be a waste of money.
I'm too busy to talk about replacing your computer.
Explain to me why we need to replace your computer.
I've changed my mind about replacing your computer.
Don't you understand what I said about replacing your computer?
I wonder if you could tell me a bit more about what's going wrong?
Could we possibly find another time to discuss replacing your computer?
I'm afraid I may not have explained myself very clearly.
I've had second thoughts about replacing your computer.
A replacement computer may not be cost effective.