I had to get a second hand motherboard to suit my CPU, and even doing that cost me about $150 AUD (or I would have been up for a new CPU and possibly RAM as well)
The graphics card I bought is a Radeon RX580 which cost me a little over $400 AUD. but it handles playing the newer games a bit better than the old graphics card that I had.
at the current exchange rate, it worked out to be a little over US$400 to repair
I had been trying to save up enough to upgrade the whole system, but my savings at the time were lacking for a whole system build, so I had to hunt around and get parts that were compatible with the parts I had left from the old system to get it running again.