Activity Monitor shows less RAM - ECC errors

I have a Mac Pro 2,1 (late 2007) running OS 10.6.8. I recently upgraded my RAM

I Installed another 16GB of RAM on top of the 16 I already have. It was fully compatible, installed as advised by Apple).

When I turn on the computer, The System Profiler says that I have 28GB of RAM, and memory chips are detected as installed.

However, when I run Activity Monitor (since I do a lot of heavy-lifting with some 64-bit music software), it says under System Memory that I only have 12GB!

I guess it's an error in AM, however if it's detecting RAM getting filled, I'm worrying that this will affect my system and not actually utulizie my 28GB of RAM.

Can anyone tell me what's going on with Activity Monitor and how I can get it show my correct amount of RAM?

thanks!

Mr Mahler said:

I Installed another 16GB of RAM on top of the 16 I already have. It was fully compatible, installed as advised by Apple).

Click to expand...

Aren't you concerned that it's not reporting 32gig of ram (16 + 16 = 32)??

Sounds to me that one 4gig stick of ram is not working...or not seated properly.

- Nick

Take the modules out, reseat and try again.

Note dodgy modules in System Profiler.

Sorry - I indeed have 28GB (Since 6x4GB chips, 2x2GB - see attached).

Since my first post, I noticed ECC errors in the System Profiler. It was on 2 chips - a 4GB chip, and a 2GB chip. Both in Riser A. I called the company who sold me the RAM (who had already returned the new batch (16GB) of RAM due to Kernel Panics previously). They said I should systematically take out RAM until I narrow down which chips are giving me the ECC Errors.

I went through and tested each pair of chips (doing clean reboots every time). NONE gave me errors. I then had 28GB in System Profiler, with NO errors (and Activity Monitor was back to normal, showing 28GB).

HOWEVER, this morning it's now showing an ECC error on a chip in Riser B !! This is NOT the same chip as before (and on a different Riser).

While my system seems stable so far (no weird crashes), I am worried that this is the symptom of a bigger problem. Can anyone shed light on these ECC errors and whether it's something I should be concerned about?

In light of what you said about the Activity Monitor bug in OS 10.6, can I assume that these issues are unrelated?

Would sending the RAM back (even though there are no crashes etc) be a good idea, or am I just as likely to get ECC errors with the replacement RAM?...

Thanks!

Mr Mahler said:

In light of what you said about the Activity Monitor bug in OS 10.6, can I assume that these issues are unrelated?

Click to expand...

Who said this?

- Nick

Sorry that was from Mac Rumors forum.

Here is the current situation on my System Profiler.

Trust you did purchase the modules from OWC or Crucial who are Mac specialists? PC memory not the go alas.

No I purchased them elsewhere, although by the book, the RAM is supposedly fully compatible....

Not if if comes from a non-Mac seller. Found this out many times by trial and error particularly if you purchase from eBay or used memory.

Yes I guess I've learned my lesson!...

I think they ONLY do exchanges (no refunds).

It's now showing two ECC Errors (On Riser B, Dimm 2 & 3). However my computer (so far) seems to be working fine.

Is it ever the case that someone can have ECC errors without actually having any bad consequences? Or is this symptomatic of a potential disaster?...

Ram for Mac Pro's (especially the early 1,1 and 2,1 models) need very specific ram...that's why we recommend getting the ram from OWC or Crucial.

Does your Mac Pro's ram look like this (below)?

Also...these 4gig ram modules cost about $90 dollars each ($180 for 2 x 4gig). If you paid a lot less than this...it's probably not the correct ram.



- Nick

Yes - my RAM looks like that. I triple-checked the specs and they were identical to Crucial's RAM.

I paid $80 for each 4GB....

Is there something about the "heat management" which the "non-spec" RAM is lacking?

Also, I was under the impression that the only officially "approved" by Apple RAM was that sold by Apple. All other companies say they are "approved", but why would Apple really approve any other companie's RAM but their own?...

I upgraded memory in that same Mac a few years ago. The issue I ran into was that most vendors were selling chips with the right specs except that they were not "fully buffered". Took me a while but I found the right chips. Managed to pull them when the machine went bad last year.

Mr Mahler said:

Also, I was under the impression that the only officially "approved" by Apple RAM was that sold by Apple. All other companies say they are "approved", but why would Apple really approve any other companie's RAM but their own?...

Click to expand...

The main point is...get the ram from OWC or Crucial...and it will work.

- Nick

I also wanted to mention. Maybe the ram you did buy was the correct ram...and the ram module that is bad...is simply a defective module. Return it & get another.

- Nick

When the very first Mac Pros came out there was articles all over the new and one somewhere on Anandtech where they found that that ram really gets hot and needs proper heat spreaders. That might be the issue with the non Crucial/OWC Ram. Just a possible guess and also what Sly said above.

Please let us know what ends up solving it.

Ok thanks folks.

Just to add confusion, since this morning (with no other changes to my system), I now have NO ECC Errors!...

If they crop up again I'll definitely replace the RAM and let you guys know.

cheers

Just looked at my System Profiler, and the ECC Error is now on an entierly different slot.

The conclusion I've come to is that this RAM, which is all from one company, despite being bought in 2 batches (a couple years apart), is randomly giving me ECC Errors. Therefore, due to the unpredictability of these errors, I have to conclude that ALL the chips are "bad" - or at least causing ECC Errors.

I don't assume this company will simply refund my money - just replace the chips. However they'll probably replace them with chips from the same or similar supplier, which implies I'll get similar ECC Errors in future.

Do you think it's worth replacing all this RAM (from the same company), or should I just live with it? So far, there is no noticeable problem on my system (kernel crashes etc), so it might be something I could live with, assuming nothing bad goes wrong in the future that's memory-related... I guess my biggest fear would be that this "bad" memory cause bigger problems (e.g. in Motherboard / hard Drive) which could be really bad...

Thoughts?...

I recommend replacing the modules from the original supplier that you purchased them from, of course assuming they will replace them for free. Typically, suppliers get their batches of memory from various manufacturers at different times. Unfortunately, ECC memory is expensive and not easy to find and spending more dollars to replace the modules from a different supplier is not really economical.

I'm now getting EEC errors on all 8 chips, though with no apparent pattern or logic.

I'm pretty sure it's the RAM. Company has offererd to replace it for free, however I've a strong suspicion I'll just get more RAM with EEC errors (i.e. they'd use the same supplier(s).

Do you think it's worth replacing all this RAM (from the same company), or should I just live with it? So far, there is no noticeable problem on my system (kernel crashes etc), so it might be something I could live with, assuming nothing bad goes wrong in the future that's memory-related... I guess my biggest fear would be that this "bad" memory cause bigger problems (e.g. in Motherboard / hard Drive) which could be really bad...

Thoughts?...