I have a dual 3.0GHz Mac Pro 1,1 running Lion. The majority of the time I start or restart the machine, the video card simply does not send data to the monitor. The machine (including the video card fan) powers up and I know it's working fine because it will play sound from reopening Chrome tabs. However, the monitor won't come out of sleep. Thinking the monitor was wonky, I tried another monitor and it does the same thing. Next, I plugged in both monitors and it will often boot up and display my extended desktop onto the second monitor, but not my main desktop. I can move my mouse over to the second screen and see it's working. If I turn off the main monitor, it will put the blank screen onto the second monitor (as it became the main) and put it to sleep. It doesn't appear to matter if it's a hard reset (holding the front power button or unplugging the cable) from cold or warm. I've both left it cold for days before trying it as well as trying it over and over. I've cleared the PRAM and all those various finger salutes. I've blown dust out of the machine, I've physically removed the card to blow dust out, I've even removed all but one pair of memory. Every once in a while, it will boot up just fine the first try. Or, after a dozen power cycles, I get lucky and it boots properly. Luckily, it's solid for months on end, otherwise I'd be driven more crazy than I am. I purchased the machine as a refurb, so though it does have the dreaded X1900XT, it was not covered in the recall (too new, IIRC) and this issue doesn't seem to be what people were experiencing. It's never glitchy or shows weird colors. When it chooses to display, it displays perfectly. How can I test to see if it's the video card without purchasing a $150 card that's half the value of the machine over at Macvidcards? What should I try first?