C2D Mac mini intermittently won't boot

[alFR]

I've got a mid-2007 Core 2 Duo mini at home that I run as a server. For the last couple of months it's not been booting reliably: it will turn on, you hear the drive eject noise that you usually hear at startup then that's it - no chime, no rest of the boot sequence. Attached monitor is black (will actually power down into sleep), suggesting that none of the display hardware is active). It does this whether being manually booted or booting on a schedule (using DSSW Power Manager software).

Usually when it does this it can be booted at a second attempt by holding down the power button until it turns off then pressing it again to turn it back on, but sometimes it takes several attempts. I did think it was related to whether or not it had an external USB drive plugged in, but in testing last weekend it will still boot with that drive attached (sometimes) and won't boot sometimes without it attached. I can't seem to establish any pattern to when it will/won't start.

I've reset the SMC and PRAM, no help. I've checked the boot drive assignment in System Preferences, which is correct. Anyone got any other ideas? Hardware dying?

 

[S.B.G]

It could be an issue with the power supply. Can you swap it out with another one to try it?

 

[alFR]

Don't have access to another one, sorry. If it was an issue with the external supply though, wouldn't it never come on at all rather than intermittently?

 

[S.B.G]

No, powers supplies can exhibit that behavior too. I had an iMac G5 did did what you describe. It would power on sometimes and other times it would not. I put a new PSU in and all was well again.

 

[alphaod]

There are many reasons that a computer doesn't boot. Since it seems to power on (since the disk drive seems to do something), I would start other diagnostic. The first step is verify if the RAM is still any good. Perhaps do a swap of those? The unreliable RAM will cause issues with boot and since the video card uses shared memory, you would have this issue. This issue perhaps you can buy RAM from somewhere with a good return policy like Amazon and try it.

Have you tried running hardware tests?

 

[alFR]

Extended hardware test (incl. RAM) runs fine, so it's not that. It did something else odd yesterday: I plugged in a USB drive and it recognised it as another USB drive that I'd had plugged in earlier. Didn't think it could do that as I thought all drives had a unique ID... Anyway, I ejected it and reinserted both drives and it recognised them both fine the second time. USB subsystem dying maybe?

Anyone got any other ideas?

 

[Osamede]

You could be running into hard drive problems by now. Got to remember this thing is constructed basically like a laptop, so you're getting to the point in the curve where heating issues etc will have mounted up. Do the hardware test as described above. I'd try cloning the boot drive with a new one and see if that sorts it out.

 

[Dwhite78]

My Mid2010 C2D had the same problem, I replaced the HD with a SSD and it works fine now.