How was it fixed? Stripes and white screen - iMac 27 inch 2009

Hello all,

Yesterday my iMac stopped working correctly.

After seeing a 'checkered' display, the iMac booted with 5 vertical lines and stays in a blank screen.

I have seen multiple threads (and I followed all the advices)

My question is: How was your fixed? How much did it cost?

Thank you in advance.