Help, total ram not being recognized!!!

[hitman10]

Hi, I installed 2 x 2gb sticks of ram with the mac ram that was already installed in the computer. I checked to see if the computer recognized the ram and it did recognize it had 6gb installed.

I went to check it again today and noticed that it stated that i had only 4gb installed. I went to check the memory set up in "about this mac" option and clicked memory and noticed it recognized the 4 dimm risers that had the memory installed but the 2gb dimms were stated at 1gb each.

I uninstalled them and installed them again and checked it again where it stated 6gb of ram was installed. I thought i solved it but i just went to check it again and it is again stating i only have 4gb installed ( 4 dimm risers with 1gb installed).

Any information would greatly be appreciated.

 

[TripleCore]

If this is for a Mac Pro, while the factory install is Riser A: 1GB, Riser B: 1GB, if you add more ram, this changes. I am guessing this might be your problem. My machine is installed so that:

Riser A: 1 GB 1 GB 2 GB 2 GB
Riser B: 2 GB 2 GB

where the first pair goes in slots 1 and 2 on A, second on slots 3 and 4 on A, third pair in slots 1 and 2 on B.

Note that they are not symmetrically balanced across Riser A and B. Check your manual for more variations.

Hope this helps.

 

[hitman10]

Yes it is a mac pro. The configuration i have is

Riser a: 1gb 1gb
Riser b: 2Gb 2gb

 

[bigbird]

Yes it is a mac pro. The configuration i have is

Riser a: 1gb 1gb
Riser b: 2Gb 2gb

Flip your RAM around by putting the 2 GB sticks in riser A, slots 1 & 2, and the 1GB sticks in riser B, slots 1 & 2

 

[bigbird]

If this is for a Mac Pro, while the factory install is Riser A: 1GB, Riser B: 1GB, if you add more ram, this changes. I am guessing this might be your problem. My machine is installed so that:

Riser A: 1 GB 1 GB 2 GB 2 GB
Riser B: 2 GB 2 GB

This doesn't look optimal. You aren't installing with matched pairs in upper and lower risers.
I would put:
Riser A: 2GB - 2GB - 1GB - 1GB
Riser B: 2GB - 2GB - empty-empty

That would give you 2 matched pairs in slots 1 & 2 of both risers. That's where the RAM is utilized first and fastest.

 

[hitman10]

I tried placing the 2 GB sticks in riser A, slots 1 & 2, and the 1GB sticks in riser B, slots 1 & 2 when i first installed the ram and it did not recognize the 1gb sticks, but i will try it again and wait a few hours to see if will recognize this setup.

 

[bigbird]

I tried placing the 2 GB sticks in riser A, slots 1 & 2, and the 1GB sticks in riser B, slots 1 & 2 when i first installed the ram and it did not recognize the 1gb sticks, but i will try it again and wait a few hours to see if will recognize this setup.

With that config you wouldn't have matched pairs in slots 1 & 2 of both risers. Report back after you try the above suggested config.

 

[hitman10]

Hi Guys, thanks for the info. I tried this setup and so far so good.

Riser a: 1gb 1gb 2gb 2gb
Riser B: nothing

Will purchase another 2 x 2gb sticks in the near future