Mac Pro 2008 - Ram Cards Problem

[klazer]

Hello,

I would appreciate it if anyone could help me get some insight into what is happening with my Mac.

When I start it up, the white power light is flashing and all the fans are on. After doing some research, I discovered it could have something to do with RAM. I have had 2x4GB & 4x2GB OWC Ram in there for a while.

After doing some reorganizing, looking for bad RAM, I discovered that they all seem to be fine, that only it won't boot up with both the Riser Cards maxed out.

Anyone know what's wrong?

 

[gpzjock]

2 possible issues: A faulty Memory Riser which shorts out when a certain slot is filled, or the pairs you have are not recognized as matched so it gets confused.
Follow the riser order for matching pairs as stated in the guide I linked below, start with the first pair of slots and work up, testing as each pair is added, this method should identify the unmatched pair or faulty riser slot. If this is the problem.....

http://guides.macrumors.com/Installing_RAM