Mac Pro Logic Board LED

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Mac Pro Logic Board LED

Hello,

My Mac Pro 3,1 has started acting weird on me. Random shut downs (complete power offs). I pressed the diagnostics button on the logic board and only the second LED was lighted. LED 7, 8, and 9 did not lighted up.

I found this

Led 7 Green On - EFI has configuredthe graphicscard

Led 8 Green On - All power rails are functioning

Led 9 Green On - EFI is done loading

on here http://www.scribd.com/doc/51667130/5/Identifying-Mac-Pro-Early-2008-Computers -- page 155

Does it mean that I have a faulty PSU? A new logic board is very expensive, should I buy a new one or throw it away and buy a new computer?

Could you please help me on this?

I appreciate any help I can get. Thank you!

Mac Pro, Mac OS X (10.5.8)

Posted on May 21, 2011 6:07 AM

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The hatter

Level 9

60,990 points

May 21, 2011 6:19 AM in response to Mike_Green

Sounds like you know your Mac better than most!

I assume you tried SMC RESET once and didn't help.

This is happening in the middle of work, idle, but not on wake from sleep.

There was an issue with wake from sleep freezing that was affecting early units and addressed by both EFI/SMC firmware (April 2008?) but these models do suffer from exessively high inrush current phenomenon.

And you definitely want a UPS, that is more than adequate, say 1300VA or above (depending on make etc such as APC RS or SMART or other top names).

Nothing else on the same circuit/current that might make a difference.

Mac Pro Power Supply

Mac Pro Logic Boards DV Warehouse

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