Today I turned on my Mac Pro and it never chimed and the screen stayed black. I forced it to shut down again and this time it turned on but the mouse was frozen and a little dark band appeared at the top of the screen. A third time, it turned on but after a few minutes it shut off suddenly. The fourth time it turned on and I checked about this mac and it reported only 4 gigs of the 10 gigs of ram. I turned off again and took out the ram and risers and cleaned them off and next time it reported 8 of 10 gigs of my ram.
I then started to experiment by switching modules around and it appears that the slots for dimms 3 and 4 on riser A are not reading the ram. The modules themselves appear ok when I put them in other slots.
I have two 1-gig sticks that came with the computer and four 2-gig sticks from OWC bought at the time of purchase last March.
I had them installed as recommended, with the four 2-gig sticks on dimms 1 and 2 of risers A and B, and the two 1-gig sticks on dimms 3 and 4 of riser A.
When I put the two 1-gig sticks in slots 3 and 4 of riser B the computer reads the 10 gigs, but I thought that it was not recommended to fill those slots unless the slots 3 and 4 were filled first on riser A.
I tried switching riser B with riser A and then the computer then only read 6 gigs.
So now I have it with two 2-gig sticks on riser A slots 1 and 2 and two 2-gig sticks on slots 1 and 2 of riser B and two 1-gig sticks on slots 3 and 4 of riser B. Riser A slots 3 and 4 are empty. This reads as 10 gigs.
But should I avoid doing this and just use the four 2-gig sticks in slots 1 and 2 of risers A and B or is it Ok to have the 2 1-gig stick on slots 3 and 4 of riser B while those slots are empty on riser A?
And is it likely that the slots 3 and 4 of riser A are damaged?
Also, is it wrong to just swap the risers in the computer? They look similar but the printed info on them is not identical, and when I did so, the computer only read 6 gigs, all on the top riser and nothing on the bottom riser.
Assuming that the riser A slots 3 and 4 are broken, can I get Apple to just exchange my riser A if I bring it in to my local Apple store, or will I need to lug the whole machine down there for them to fool around with?
If the riser is at fault, shouldn't they be able to check that by trying it out on another computer? And if it works Ok on their system but not on mine, does that imply a deeper problem, perhaps on the motherboard itself?
Please excuse the convoluted post. I hope it is clear enough to make some sense. I still have at least 5 or six months left on my Applecare so I am not too worried about holding off to see whether the problem gets worse and the computer develops other sysmptoms but I know that I will have to have the riser issue addressed before my warranty runs out.
Thanks for any help or advice.
I then started to experiment by switching modules around and it appears that the slots for dimms 3 and 4 on riser A are not reading the ram. The modules themselves appear ok when I put them in other slots.
I have two 1-gig sticks that came with the computer and four 2-gig sticks from OWC bought at the time of purchase last March.
I had them installed as recommended, with the four 2-gig sticks on dimms 1 and 2 of risers A and B, and the two 1-gig sticks on dimms 3 and 4 of riser A.
When I put the two 1-gig sticks in slots 3 and 4 of riser B the computer reads the 10 gigs, but I thought that it was not recommended to fill those slots unless the slots 3 and 4 were filled first on riser A.
I tried switching riser B with riser A and then the computer then only read 6 gigs.
So now I have it with two 2-gig sticks on riser A slots 1 and 2 and two 2-gig sticks on slots 1 and 2 of riser B and two 1-gig sticks on slots 3 and 4 of riser B. Riser A slots 3 and 4 are empty. This reads as 10 gigs.
But should I avoid doing this and just use the four 2-gig sticks in slots 1 and 2 of risers A and B or is it Ok to have the 2 1-gig stick on slots 3 and 4 of riser B while those slots are empty on riser A?
And is it likely that the slots 3 and 4 of riser A are damaged?
Also, is it wrong to just swap the risers in the computer? They look similar but the printed info on them is not identical, and when I did so, the computer only read 6 gigs, all on the top riser and nothing on the bottom riser.
Assuming that the riser A slots 3 and 4 are broken, can I get Apple to just exchange my riser A if I bring it in to my local Apple store, or will I need to lug the whole machine down there for them to fool around with?
If the riser is at fault, shouldn't they be able to check that by trying it out on another computer? And if it works Ok on their system but not on mine, does that imply a deeper problem, perhaps on the motherboard itself?
Please excuse the convoluted post. I hope it is clear enough to make some sense. I still have at least 5 or six months left on my Applecare so I am not too worried about holding off to see whether the problem gets worse and the computer develops other sysmptoms but I know that I will have to have the riser issue addressed before my warranty runs out.
Thanks for any help or advice.