No display and failing to boot.
I have a rather interesting problem with my iMac. A few weeks ago the screen stopped working, however I use this computer almost exclusively through screen sharing from my MacBook and it wasn't really a huge issue. I have just been on holiday and on my return the computer will now not boot. I have the boot-up sound and can reset the PRAM and get the second boot-up sound. The DVD drive is spinning up when a disk is inserted, however the computer is failing to appear on the network.
I have tried plugging it into an external display and there is no display shown. I have inserted the original installation disk whilst the computer is plugged into the external display and an image is then displayed (however I think it is set up to extend desktop - so only the background appears). I am wondering whether I now have two problems and whether these could both be linked to a cooling issue.
I imagine due to the fact that I'm getting a picture on the external display when the installation disk is inserted that the video card is working properly - does this then mean that the LCD is broken - how much is this likely to cost to replace. The screen glows when the computer is turned on and goes back black when it is switched off.
Secondly, I imagine that due to the fact the computer is no longer appearing on the network - and only appears to boot from the installation disk that my hard drive has failed. Is this a correct assumption?
Thirdly, I imagine I would be pretty unlucky to have both these failures within such a short time of each other, so are they likely to be related to a cooling issue?
Many Thanks in advance for your help
Is this a good question?