I have a small recording studio....and have been having startup problems with my early 2008 (see sys specs) Mac Pro.
Upon powering up, it shows the white screen with apple, then the spinning loading wheel (Mavericks), then peripherals come online (audio interface, security keys, etc.). But then there is a long pause, and the apple reappears. The desktop never seems to start. Sometimes behavior varies slightly. Sometimes there will be a spinning beach ball, or the dialog 'You shut your computer down because of a problem....' will appear. But there is next to no responsiveness. After many reboots, what I discovered is that the system's functions are actually happening, but at an ungodly slow rate. Like screen and mouse refreshes in steps. So the OS is actually trying to load, but cannot function reasonably once it starts to show up.
Safe boot does work, BTW. I've tried all the standard diagnostic procedures, tricks, etc.
Safe boot
Repair disk and permissions
Disconnecting all hardware (including internal SuperDrive)
Reset PRAM/SMC (power disconnect, boot key command, and logic board button)
Booting with only a single monitor
Apple hardware test
Emptying out the startup programs
Now HERE'S THE TRICKY PART. Sometimes after hours of trying, the system will eventually boot correctly, and work perfectly without any failure. When that happens, obviously I try to keep the computer on as long as possible....and I can use it perfectly....until I have to power down for some reason. Then it's back to the drawing board. However, I cannot figure out what is causing a successful boot up.
A few things I've been told it could be are...
Bad logic board
Bad memory
Failing system drive
Bad video card
Bad power supply
I recently had the video card replaced. Same as original...(I know. I way overpaid)...and the tech said the card and the 1st PCIe 16x slot it was in were both fried. But the new card was installed in the 2nd slot, and was working fine when it left the shop. All the diagnostics have checked out OK. Even the extended (longer) Apple hardware test.
One last note is that I also have Snow Leopard installed on a 2nd partition. Used to work fine....but now has the same problem. Will not boot up reliably either.
Anybody have any other ideas? I'm perfectly willing to work on this thing. We inherited the tower...and it's a lot better and more powerful than I can really afford. But I do not want to throw money into it that doesn't need to be. Currently NO budget for a new machine...and if this one dies, it's back to docking my MacBook Pro....which really SUCKS.
Would appreciate any further advice or tidbits. Thanks.
B
