iMac freezes, then will not start up???

[Andy2010]

I have an iMac DV400, if i leave it on but doing nothing after about 2 hours the mac freezes. When I reboot it there is nothing, the light comes on but that is all. If I then leave it for a couple of days it works again. Any idea what is causing this?

Thanks

 

[varmit]

I have an iMac DV400, if i leave it on but doing nothing after about 2 hours the mac freezes. When I reboot it there is nothing, the light comes on but that is all. If I then leave it for a couple of days it works again. Any idea what is causing this?

Thanks

Ok, first off, what OS? 10.2 or 10.3, or is it OS 9? Second, reset as many things as you can, that means PRAM, PMU. Might also want to get the latest firmware update for your particular Mac, and run it because I have seen this, when a Mac doesn't have the right firmware for the OS that is running on it. If there is a hardware test disk, run it and see if it picks up any problems with the hardware.

So you have the computer go to sleep after 2 hours, or have the hard drive spin down after 2 hours of no use? If so, I would change that setting. Another thing that might be a problem is third party RAM that was not installed by Apple, it has been known to cause conflicts. Also, was was the last thing you did before this started to occur? Install a program or change a setting, or even hardware replacement?

 

[Andy2010]

Thanks for your help. I am running OS 9.2.2, I have installed extra RAM which is 3rd party, how do you reset PRAM?

 

[maya]

Thanks for your help. I am running OS 9.2.2, I have installed extra RAM which is 3rd party, how do you reset PRAM?

Click THIS, it should help you step by step.