Why is my G5 suddenly reporting 1 GB less RAM???

[FMiguelez]

Hello.

I've had 4 1-GB sticks in my G5 for years now. I even have a picture of it reading 4 GB.
Today, suddenly, the About this Mac reads it only has 3 GBs.

If I go under More Info, it reads as if I have 2 1-GB sticks and 2 512-MBs sticks, summing only 3 instead of 4.

I ignored it, and I was cloning an HD with CCC, and then the computer froze with a frightening message I had never seen. I took a picture of it with my iPhone, but won't be able to upload it until later.

How can this be?

Perhaps the memory is getting bad. I am running Rember at the moment. It's taking too long...
But if the memory is failing, wouldn't it just fail and not report 2 dimms with only half of it?

[cuttime]

Was it the Kernel panic?


Yeah, you have a RAM problem for sure. Rember is the way to go. You may be able to salvage the situation by merely re-seating the RAM after cleaning the contacts. Good luck.

[FMiguelez]

Hi, CutTime.

That's EXACTLY what I got! The text was a little different, but it looked like that.

Rember is still running... I'll post back when it finishes testing.

Thanks!

[FMiguelez]

Hmmmm.... That's weird!

Rember said it passed its test successfully.

It is strange how 2 dims report half their memory only. And I can't believe I've had this for at least 4 months. I just found a screenshot dated 5 months ago with the memory reporting only 3GB, and I never noticed it until now (because of the kernel panic)

[Tritonemusic]

Once, my old G4 showed only half of the RAM that was actually installed. I pulled the RAM sticks out, and reinstalled them. That fixed the problem. I know it sounds like a long shot, but I'd give it a try. You never know.

[FMiguelez]

Hey, Tritone.

I will try your suggestion. I'll even shuffle them and see what happens.

Thanks!

[mikehalloran]

The G5 uses matched pairs of RAM. If one stick goes bad, neither will show. If you have accidentally mismatched a pair, it may show a matched pair of the lower value or may show nothing at all.

Go to About this Mac. In the report, it will list the RAM by slots. Compare what is reported vs what is installed. The slots are labelled on the motherboard if you look carefully.

You might try burnishing the contacts. Remove and reinstall the RAM a couple times - sometimes this will clean the contacts and bring it back to life.

If all your RAM has the same value, you can play with swapping it around and, by process of elimination, figure out which stick is bad.

I probably have some G5 RAM around here. No idea if I have labelled it correctly and I don't have my old G5 around to test. I will check, however, in case the stickers are readable. Do you have 184 or 240 pin RAM?

[FMiguelez]

The G5 uses matched pairs of RAM. If one stick goes bad, neither will show. If you have accidentally mismatched a pair, it may show a matched pair of the lower value or may show nothing at all.

Go to About this Mac. In the report, it will list the RAM by slots. Compare what is reported vs what is installed. The slots are labelled on the motherboard if you look carefully.

That's the thing. Every time I upgrade a computer component, I always create a new System Profiler file with a date.
I KNOW the computer used to show the 4 GB correctly. Apparently a few months ago, without me noticing, something went wrong and it started showing only 3 GB (now I understand why I felt my computer getting slower... I just attributed it to more complex projects).

And to make matters worse, yesterday, sometime during doing my annual backups, another thing went wrong and now the computer shows ONLY 2 GBs
They show under System Profiler as 2 sockets with 1 GB each and the other 2 empty (a few hours earlier they showed 512 MB each of these two).

You might try burnishing the contacts. Remove and reinstall the RAM a couple times - sometimes this will clean the contacts and bring it back to life.

If all your RAM has the same value, you can play with swapping it around and, by process of elimination, figure out which stick is bad.

I probably have some G5 RAM around here. No idea if I have labelled it correctly and I don't have my old G5 around to test. I will check, however, in case the stickers are readable. Do you have 184 or 240 pin RAM?

I will definitely try burnishing them tomorrow morning and see if that fixes it, but the fact that I had a Kernel panic, plus these memory-reading anomalies, make me think that it's probably time to replace the memory (or computer all together)

I can't understand how this can happen! Therefore, it must've been Loki (Hveðrungr)

[MIDI Life Crisis]

It's time, Fernando. I see a Mac Pro in your future. I wouldn't throw another penny at a G5.

[FMiguelez]

It's time, Fernando. I see a Mac Pro in your future. I wouldn't throw another penny at a G5.

Totally agreed, Mike.
Actually, it has been time to replace my G5 for at least 2 or 3 years now!! (I've survived thus far thanks to the slave computers)

Last year wasn't great project-wise. But there's a 97% chance I will be able to upgrade my entire system (computers, software, screens and audio interface) within the next few weeks.
FINALLY!!!!!

If I'm able to do that, then this G5 would serve me perfectly well just to host a couple of VIs that I'm not ready to give up yet (they don't work on anything later than Leopard). Or maybe even donate it to my parents

[MIDI Life Crisis]

Even with my lowly 2008 MP, I don't need to host or even bridge any VIs. Multi threading does the job. Complex VIs get their own channel as per MagicD. Sell the dog. Sell the car. Live on the street, but update, man. You're too good not to.

[mikehalloran]

If half of a 1G stick goes bad, that's the only way that your G5 will show 3G - the corresponding bank on the matching slot will only show half, too. If the rest of that same stick goes bad, neither half of the good stick will show. G5 RAM must be matched.

Your profiler will show you which slots have good RAM if you drill down. Say 1,2 show good, 3,4 show empty but have RAM installed. Swap 1 & 3. If 3,4 now show good, the stick in 1 is bad. If there is no change, 4 is bad. If the computer doesn't boot, 3,4 are both bad (extremely rare). If all 4 show good, dirty contacts on 3 was the problem. And so on...

If the slots are bad, you still have two more pairs as your signature shows a dual CPU G5.

[FMiguelez]

Ok.
I switched and shuffled all 4 sticks. In one position it shows 2 GB only (2x1 GB and 2x0), and in the other one 3 GB (2x1 GB and 2x512 MB).

So it looks like the sockets are fine, and 2 sticks are fine. The other 2, the ones that report only half of their capacity, are the weird ones.

If I decide to keep this computer as a vintage "be-able-to-use-old-unsupported-VIs", then I'll buy a pair of RAM sticks from OWC.

Thanks guys!

[MIDI Life Crisis]

Unless it's the original RAM it might be covered under a lifetime warranty. RAM frequently is.

[mikehalloran]

The other 2, the ones that report only half of their capacity, are the weird ones.

this doesn't mean both sticks are bad. Most likely, one bank of one stick is bad. This will cause the corresponding bank on the other stick not to show. Not weird. G5 RAM only works when the pairs matched.

What happens when you put those two sticks on another pair of slots?