Dual 1.25 Powers On But Does Not Boot

[sethkj]

I recently got a Dual 1.25 MDD off of eBay which describes as a restoration project. The system powers on but no chime. After about 10 seconds, the fans go full blast. I've done the following:

- Replaced PRAM battery
- Reset PMU
- Reseat video card, RAM, and power supply connector to motherboard
- Removed all PCI, RAM, video card and optical drives and test machine - no boot.
- Reseat CPU and heatsink
- Took out the motherboard to check for corrosion (There is none)

Does this sound like a power supply issue? The red light on the motherboard turns lights up and I can't get any power from the USB (keyboard is non responsive). What other steps I can do to rule out the CPU, motherboard or power supply? The PSU is the Samsung model. I've read it's prone to fail. Any help is greatly appreciated!

 

[mustagcoupe]

Did the seller say if it was working or not, you said it was described as a restoration project, to me that suggests it might have problems the previous owner was unable to fix. I would start by taking a closer look at the memory first. Have you tested the ram or tried one stick at a time. If you just removed and re-seated them that wont do anything about a bad stick. Did you check the cpu socket on both the logic board and the cpu board for corrosion or bent pins. Are all the power connectors fully seated and all of the wires are in the connector, sometimes the pins can get damaged and forced out of the connector so they dont make good contact. I would pull the power supply out and remove its cover to check its internal condition, make sure its not full of dust and there are no visibly bad capacitors. Removing the cover to look is safe as long as its unplugged from the wall, just dont touch any of the internal electronics on the power supply unless you know what your doing, you could get shocked or killed even if its unplugged.

 

[sethkj]

Thanks @mustagcoupe for responding. After swapping parts and doing a process I’d elimination, I’ve narrowed it down to a mess up CPU card and motherboard. While I would love to keep the FW800 machine, I just don’t see putting anymore money into it. I still have a single CPU 2003 MDD that I’ve put all the good working parts into. At least now I can add tearing down and putting together a nearly 20 year old computer on my resume 😂

 

[mustagcoupe]

Are you sure its both the cpu card and the motherboard, thats not that common. Have you tested both with the working units power supply. If its truly dead you got yourself a bunch of spare parts for the working unit.

 

[sethkj]

Are you sure its both the cpu card and the motherboard, thats not that common. Have you tested both with the working units power supply. If its truly dead you got yourself a bunch of spare parts for the working unit.

Yeah - the two machines I have are:

- FW400 MDD with single 1.25 Ghz and AcBel PSU - works well.
- FW800 MDD with DP 1.25 Ghz and Samsung PSU - does not work.

This is what I've done so far:

I've tested both the FW800 motherboard and its DP CPU card with 2 different power supply (Samsung and AcBel). No boot.

I put the single 1.25 card in the FW800. It does boot and chime but I get the question mark. Tried booting just the CD drives with an OS on it. Question mark. Tried booting from a known good hard drive. All Master/Slave promoters are set correctly. Still a question mark with a folder. My assumption is the board does not recognize the optical and hard drives attached, even though the optical drives are responsive (i.e. opening and closing, spins up and tries to read, etc.). I even went into open firmware and reset the nvram. Performed Command+Option+P+R. Nothing changed.

I decided to move all the devices over to the known good FW400 machine. After hooking everything up with the single 1.25 CPU card, it booted up with an existing copy of OS X. I decided for giggles to try the DP CPU card in its place. All it does is turn on, fan will go full blast after about 10 seconds. I reseated the CPU card and put fresh thermal grease/paste on it.

Now that I got a chance to look at it again, I noticed the CPU card is warped. Therefore, it may not make full contact to the motherboard. I'm also questioning why the FW800 motherboard boots and chime but does not recognize any devices (CD/HDD). Looking at the board again (taken out of the case) I couldn't find any water damage or corrosion. I can't tell if there are any blown capacitors. I did, however, found rust on the shield that holds the CD's data and power cable (above the lower fan).

I've uploaded some pictures of the board and the CPU card in question:

 

[mustagcoupe]

The fact that it boots up to a question mark with the single processor card is a good sign, it means it cant detect an operating system. Try holding down option to get to the boot picker and see if anything shows up. Did the known good drives have an operating system on them. The fw800 model will not boot os9 with the stock firmware. If you are trying to boot it from an os9 disk it will not work. It also will not boot from an osx installation older than either 10.2.3 or 10.2.7, i cant remember which. Did you try a known good optical drive in the fw800. Older optical drives can get really flakey and weird. I would also connect and disconnect the hard drive and optical drive cables from both the drives and the logic board a couple of times. It looks like that computer was stored in a humid area and may have some corrosion on the pins that will get scraped off doing that. I would also try the cables from the working unit and set the jumpers to cable select instead of master/slave. If none of that works try doing a pmu reset, press the button labeled pmu reset next to the ata-66 connector on the motherboard. PRESS IT ONCE AND ONLY ONCE pressing it twice or holding it could mess up the power management unit. If you still dont get anything a pci ata/sata card could get it working if only the hard drive busses are fried. I highly doubt all 3 ata busses are fried as they are controlled by 2 different chips but stranger things have happened. That dual processor card looks like it may have gotten very hot, that thermal paste looks roasted. You said its warped, it might not have been making good contact with the heatsink and cooked itself to death. If you manage to get the fw-800 unit going again replacement processors arent that expensive.