I've had a blank-screen problem with my ATI Radeon X1900 XT graphics card (MacPro) since Snow Leopard came along. It's interesting to hear about AMD's purchase of ATI and their subsequent seeming inattention to Mac OS X. As best I can tell, the problem is related to SL's upgrade to 64-bit processing and its Grand Central Dispatch (that efficiently distributes processing among available CPU cores). Both of these features speed up all processing, and particularly startup. In essence, SL starts up (or wakes up) quickly enough to blow by the point at which it should link to the graphics card before ATI has had a chance to warm up to operating temperature (or before the ATI software reports that it is ready). As a side note, the problem seems to be somewhat lessened by the seasonal higher ambient temperature in my apartment (I'm a smoker and, except for air conditioning periods, have at least one window open all year).
I hoped that the 10.6.3 update would resolve the problem. It hasn't. I previously informed Apple of the problem and was told that it seemed to be related to "timing," yet it didn't get fixed. Apple writes many of its own drivers to provide consistent, integrated performance. It seems that Apple has not updated (or written?) its drivers for ATI graphics cards.
I approached this problem with Apple through
http://www.apple.com/support/expert/. Actually, I had two problems – the other related to Automator. The Automator issue was resolved by a Security Update. No such luck with the ATI question. The "expert" webpage is remarkable. It allows a Mac user to state a time at which Apple can telephone you. They were spot on for both of the questions that I asked – a timely call to me and expected follow-up. Eligibility for such support is the purchase of an Apple product within 90 days. They're not trying to defeat inquiries. My purchase was SL. Since I have an Inquiry Number, I could probably pursue the question. But, rather than my being the typical nuisance, often described as the little blue-haired old lady from Pasadena wearing tennis shoes, it would probably be better for there to be multiple inquiries expressing cumulative facets of the issue, Best to have the question well formed!
Good luck to us all!
