I have just bought an AppleTV off eBay and I am trying to test it to make sure it works, but I don't currently have a flat screen TV to try it with. I have a couple of good TFT computer monitors but both are VGA so I bought a HDMi to VGA cable off eBay which arrived this morning and neither monitor gets a signal and just displays 'Check cable connection'. What's this more likely to be? A problem with the cable or the AppleTV? Can anyone suggest any other way of testing this?