Need help with Mac Pro Boot issues

[redrex]

So I had this thing dropped in my lap and I don't know a whole lot about Mac's. Which is sad because I was an IT manager for 15 years

So, here is what I know. It's powers up, chimes but does not display any video.

I've tried replacing the video card with one that I had but that doesn't seem to do anything. Honestly though I'm not sure that the video card was good to begin with

Here is another piece of info, useful or now. The memory card risers have led lights on them. When I first began trouble shooting this, on card would light up and one light would stay on but on the other card nothing. Now neither card lights up. I'm thinking that this could be a case of bad memory.

Any suggestions.

[Rivers]

First, remove all unnecessary cabling, like USB printers, etc. If you have a bootable Apple DVD, boot from that (hold C key down on startup.) You can run Disk Utility from that once the menu bar at top appears. If it displays anything normally, your hardware is likely fine. If not, possible hardware issue. Try different external monitors and cables to remove that as a possibility. If all else fails, it could be video cards. How old it the MP and is there AppleCare coverage? Even if outside of AC, if there were known issues with any components that go bad after AC expires, Apple will typically make them right. You may need to have your serial number handle for a web lookup on Apple's site.

[hcbr]

do you know what model this is? you can get the serial and see which one it is (2006, 2008 early 2010, etc.)

I can elaborate more , but can't exactly tell what's going on.

[redrex]

Rivers - Yeah, I've isolated it, keyboard, mouse and video only. I've tried two monitors and I've tested the cable as good. I actually have a whole PC test bench setup, so I've gone through all the basic testing. There is no AC on this. This unit was left behind in an office when a tenant left town in the middle of the night. And now I know why

Hcbr, this is a Mac Pro 2.8 A1188

I tried pulling the hard drive and that didn't change anything and I have swapped the video card. I'm leaning hard towards memory issues.

So here are a couple questions for you...
Does a Mac Pro need two memory sticks to boot or can it boot off of a single stick?

[sfwdiy]

Rivers - Yeah, I've isolated it, keyboard, mouse and video only. I've tried two monitors and I've tested the cable as good. I actually have a whole PC test bench setup, so I've gone through all the basic testing. There is no AC on this. This unit was left behind in an office when a tenant left town in the middle of the night. And now I know why

Hcbr, this is a Mac Pro 2.8 A1188

I tried pulling the hard drive and that didn't change anything and I have swapped the video card. I'm leaning hard towards memory issues.

So here are a couple questions for you...
Does a Mac Pro need two memory sticks to boot or can it boot off of a single stick?

Depending on the model it'll boot with one RAM chip. If you're hearing the chime on startup, that means the unit is passing POST, or the Power On Self Test. In order to get a boot chime on a Mac you need a functioning logic board, processor and memory.

If your RAM was bad or misconfigured you'd be getting three beeps on startup instead of a chime.

You can't just swap a video card on a Mac Pro. OS X only has drivers for a few specific cards that Mac Pros could be configured with from the factory.

Try re-seating the original card. Then, with the unit unplugged, hold down the power button for about 20 seconds. While still holding down the button, plug it back in. Release the power button, then press it again to turn the unit on.

If you get no video after that, shut it off again. Then power it back on while holding down the 'command', 'option', 'P' and 'R' keys on the keyboard. You'll hear the boot chime, then it'll seem to power down and restart itself. You'll hear another boot chime. Keep holding the keys 'til you hear three chimes. Let it boot up all the way, see if you get video.

--B

[kwansao]

Try holding down Command option p r on startup. Keep it held down until you hear 3 chimes. That might help.