So I received a 2006 a1186 mac pro from family. It was working initially, and I had it updated to snow leopard.
Had a bit of a problem though that occurred. I was taking the optical drive out of it and noticed the molex connector that was in it had its end cut off (it is supposed to have 2x 4pin molex connectors but only had one. I didn't think much of it but when I went to start it back up the cable sparked because it had touched the casing. This immediately caused the mac to shut off.
After that it wouldn't boot. I don't even get the chime. Had no power on diagnostic LED until messing around today, trickle and graphics were present though.
I needed some files from the HDD inside it, so I took it out and plugged it into my PC. This caused my PC not to boot. Smelled the drive, had a slight burning smell. It was obviously shorted out, and was causing both computers not to power on properly. Once the drive was removed from the mac, it now chimes. LED diagnostic lights turn on for trickle, graphics and power on this time.
Here's the issue though. I formatted a new hard drive to HFS+ and put it in the mac pro. Turned it on, no chime this time. Trickle LED, Power LED, no graphics LED. However, when the HDD is removed I get the chime AND the graphics LED turns on. HDD back in, back to no graphics LED and no chime... I have tried this with 2 different HDDs, both of which work in other computers.
I'm going to go with the obvious logic board is messed up from the short.. but I just wanted to make sure. I have two 7300 GTs and I have tried them both individually, no luck with the graphics LED coming on when the HDD is present.
Note that when the HDD is removed and it chimes, it does give me the grey screen and eventually shows the flashing folder with a question mark since no HDD is present.
Had a bit of a problem though that occurred. I was taking the optical drive out of it and noticed the molex connector that was in it had its end cut off (it is supposed to have 2x 4pin molex connectors but only had one. I didn't think much of it but when I went to start it back up the cable sparked because it had touched the casing. This immediately caused the mac to shut off.
After that it wouldn't boot. I don't even get the chime. Had no power on diagnostic LED until messing around today, trickle and graphics were present though.
I needed some files from the HDD inside it, so I took it out and plugged it into my PC. This caused my PC not to boot. Smelled the drive, had a slight burning smell. It was obviously shorted out, and was causing both computers not to power on properly. Once the drive was removed from the mac, it now chimes. LED diagnostic lights turn on for trickle, graphics and power on this time.
Here's the issue though. I formatted a new hard drive to HFS+ and put it in the mac pro. Turned it on, no chime this time. Trickle LED, Power LED, no graphics LED. However, when the HDD is removed I get the chime AND the graphics LED turns on. HDD back in, back to no graphics LED and no chime... I have tried this with 2 different HDDs, both of which work in other computers.
I'm going to go with the obvious logic board is messed up from the short.. but I just wanted to make sure. I have two 7300 GTs and I have tried them both individually, no luck with the graphics LED coming on when the HDD is present.
Note that when the HDD is removed and it chimes, it does give me the grey screen and eventually shows the flashing folder with a question mark since no HDD is present.