Mac Pro 2006 won't reboot

[izzy0242mr]

I just got a 2006 Mac Pro and I'm having trouble with it rebooting. Been a problem ever since I ran the Lion installer: when it's given a reboot command (either directly, or via a software update prompt), the external monitor will turn off and the computer will look like it's turning off, but the power light on the front stays on and it doesn't fully shut off OR if it does it doesn't start back up. I have to hold the power button down and then press it again to get it to reboot.

Felt a bit risky when I had to do that after some software updates, but it booted up just fine. The problem is that it seems to hang somewhere between receiving the reboot command and starting back up again. The same problem occurs when I issue a reboot command from Windows. Any thoughts?

 

[Sko]

You didn't give much information about your setup, but from your screenshot 22 GB seems a little odd. I had restart issues caused by bad RAM. Is 22 GB the expected amount? Do your RAM-raisers have any red lights?

 

[haralds]

I just got a 2006 Mac Pro and I'm having trouble with it rebooting. Been a problem ever since I ran the Lion installer: when it's given a reboot command (either directly, or via a software update prompt), the external monitor will turn off and the computer will look like it's turning off, but the power light on the front stays on and it doesn't fully shut off OR if it does it doesn't start back up. I have to hold the power button down and then press it again to get it to reboot.

Felt a bit risky when I had to do that after some software updates, but it booted up just fine. The problem is that it seems to hang somewhere between receiving the reboot command and starting back up again. The same problem occurs when I issue a reboot command from Windows. Any thoughts?

Could be a hanging process. I would try another install of Lion.

 

[izzy0242mr]

I had 4x 4GB of Samsung RAM + 4x 2GB of old RAM with heatsinks on it, hence the 22. I just got 4x more of the Samsung RAM so it's at 32 GB.

Two 3 GHz Xeon 5160 chips, X1900 GPU, 1 TB hard drive with Lion installed, another TB drive with 500 GB devoted to Boot Camp (which I installed on another computer since I wanted 64 bit Windows and didn't have a DVD to burn/mod and then transferred in the hard drive, which means that while I can choose Windows via option key at boot, but Windows doesn't show up in the Startup Disk pref pane). Boot Camp is running Windows 7 Basic upgraded to Windows 7 Home Premium upgraded to Windows 10.

@haralds I would think so too except it has the same issue when I reboot from Windows, so I am not sure.

I'm wanting to upgrade to El Cap but am still needing to find a cheap graphics card that is compatible so I can use the bootup chooser.

 

[CapnDavey]

As far as the graphic's card goes most ATI 4870's are easy to flash with a mac rom .they work well in the older mac pros with a newer system to and they can be had cheap

 

[Sko]

I had 4x 4GB of Samsung RAM + 4x 2GB of old RAM with heatsinks on it, hence the 22.

You do realize that this should be 24, don't you? Again, for me bad RAM caused this, no restarts on Mac OS, shutdown was fine, Windows didn't restart or shutdown.

I was using a flashed 4870 for boot screen but replaced that last year for a R9 280X, link for flashing that is in my signature.