Hi there,
I just came across your comments & was very interested for the following reason. I bought a refurbished MBP 15" with the infamous NVIDIA GeForce 8600M GT graphics processor 1 year ago from Ireland's first Apple reseller. I put it to sleep on Saturday night & on Sunday when I tried to wake it, nothing happened.
Despite several attempts, I could not get the laptop to reboot. I brought it back to seller & they just said sorry but it needs a new logic board at +/- 1000 dollars! They offered no explanation regarding the issue with the graphics processor, instead, I discovered this problem through an internet search.
I emailed & rang the company today & the guy said he tried to test my machine but as it didn't even get to the chime, he was unable to diagnose the problem. The thing is, he claimed that becaues it didn't even get to the chime, it could not be a problem with the graphics processor.
Now, I read your comment & case 3 above suggests to me that it could indeed be what caused my computer to stop working. I am so angry & disappointed by this Apple resellers lack of customer care or service. I explained that 12 months usage for a machine is UNACCEPTABLE but he was dismissive & uninterested in exploring properly the possibility that this admitted issue could be the problem with my MBP.
To conclude, I was wondering whether you had any further news regarding the 3rd scenario you mentioned, i.e. where the chime doesnt even come on? I see you suggested that it might well be the graphics processor behind the problem?
I am even reluctant to give this guy my machine to test it further because I don't now trust him to give a truly objective account of what the problem is? Its almost like he would have to personally pay to fix the problem. So i'm left unable to deliver my course & having bought numerous Apple products over the past decade as well as advocating them to my numerous students here, I find myself warning students off Apple products as opposed to highly recommending them as in the past.
Thanks for any relevant info you might have & greetings from a sunny Dublin, Ireland.
Derek