If you want to finally modify your GameCube for a crisp, clean, HDMI output BadAss Consoles finally has various modkits up for preorder. They have both analog and digital options up to ship in mid-October, with installations available for around $40 USD. http://www.badassconsoles.com/gcvideo-1/
The eBay component cable scalpers can finally be stopped!
The eBay component cable scalpers can finally be stopped!