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cs.oyen

macrumors member
Original poster
Sep 1, 2015
39
3
Portugal
Hi guys!

I'm facing a problem with an Mac Pro 1,1 (2006).

First of all let me give all SW and HW specs:

- The computer itself is a Mac Pro 1,1 but was flashed to be recognized as an 2,1 (2007);
- The installed CPU's are two E5345 @2,33 GHz;
- The GPU is and HD5770 flashed to work as an Apple version.
- Have 8GB RAM (1GB*8);
- Storage 2 SSD's (raid) and 1 HDD to backup;
- Have El Capitan installed (not natively supported).

It's all I can remember now.

I know that is a very old machine in terms of computers age, it's outdated and ultimately one day (maybe now) will stop working for many reasons. To be honest, I have it and still use it because even today it works fine and at this time never got me troubles.

Let me explain whats happening:

- Yesterday I needed to install on another disk an old version of OS X, I have a flash drive with Lion so try to install it.

- Do everything as normal for new installations but for any reason I don't know when installing Lion the computer just restarted, and give me a screen what I think was a kernel panic.

From that moment the disk with El Capitan got many random restarts. Some with kernel panic other was just a "simple" restart.

Tryed to install Lion again, it worked fine but I check that it just recognize 6GB of RAM instead of the installed 8GB. Reboot to El Capitan and still recognize 6GB of RAM.

- I opened it and checked that one of RAM riser cards (the riser A), when boot stay with a continuous red light. It just recognize the ram modules into ram slot 1 and 2. The slot 3 and 4 just don't detect the ram modules.

- After running many tests I can't see any problem with any ram module. I think the problem is that specific ram Riser Card but at this is the first time that happens to me I don't know exactly if is just that or have more unknown problems.

So in your opinion, it's possible a ram riser card become faulty at two of the four ram slots or I'm away of the real problem?

Sorry for my bad English.

Cheers!
 

cs.oyen

macrumors member
Original poster
Sep 1, 2015
39
3
Portugal
EDIT:

After a few time thinking about this I remember to check one thing I never do before. Clean the ram and riser card slots.

With an brand new white rubber I cleaned all the connectors and apply some air duster to remove all the remaining residuum.

After this procedure OS X recognizes again all the installed ram dimms.

Ran Apple Hardware Test too for about one hour and no issues reported. Tryed to install again El Capitan and now installs and works fine.

For people with this problem may this steps can give some help.

Cheers.
 
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