1 Gig sdram Saga

I bought a 1 Gig PC133MHz ECC Reg sdram.

I requested one with 36 ICs, but got an 18 IC one. Had to wait a week to get it.

I have an AmigaOne XE 800 MHz. I'm using pre-release 4, not final.

They said it would work, and would take it back if it didn't work, so I went for it.

Well, it don't work.

The UBoot knows that there is 1 Gig of ram there, and the computer booted up. It complained that I was running out of ram at the 256 Meg mark. Turns out UBoot has a variable that limits the amount of ram used.

I selected from the UBoot menu system "boot one time in this configuration" after changing the setting for UBoot to use 1 Gig of ram.

I started filling the ram disk with wav music files (30 to 80 Megs) and at the 380 meg mark, when I added a wav of 30 megs more, the system locked up.

A shell that was running the copy command froze. I could still type, but no commands would run, and the mouse pointer could move, but nothing would start, and I couldn't get any device icons to open.

Seems that, once it gets to 512 Megs, it starts writing to the first memory address again and up, until the OS is no longer functional.

So, is this what is the problem with these 1 Gig sdrams, or is it something else?


Like I said, I could run, as long as I didn't go over 512 Megs. Later today, I'm going to set it to 512 Megs and see how long I can go without crashing.

Is there no way to force it to NOT loop around and write onto address 0000 0000 and from there up again? The sound chip problem was circumvented after all.

I have no clue what the problem is, but it really looks like that's what's happening.


Avail generates what appear to be totally wrong numbers. Whatever Textclip: is, goes into 700 Megs.

If anyone wants some register dumps, just tell me how to get them out.

We all know the XE is a bit peculiar....

/speculation

RAID drives in striped mode write half the data on one drive, and half on the other, so, don't suppose that when it gets to 512 Megs of data stored in A1 XE ram, it wants to, for some unknown reason, write to a second sdram (which would also have to be 1 Gig) to, I don't know, balance the load, then after it reaches 512 Megs on that one, start again on the first?



Otherwise, is there any way to check the contents of address 0 to say address 1023, and see if it gets overwritten when it passes 512 Megs?

Of course, a small file would have to continually get duplicated in the ram disk: until 512 Megs is surpassed. At only 1 K of overwrite, the system still may be functional enough to see if the contents have been altered. This would only work if there are bytes in that address space that never change, for comparison purposes to see what's happening.


This may have all been done before, I've never read anywhere what the issues were about this problem.

PM me with some info please, if this is not something that is meant to be public. I'll keep it in confidence.


Like I said, maybe this is resolvable, like the sound chip problem was?

@Atheist

Nothing so difficult. Many people are using 1 GB RAMs, I know one person using two 1 GB RAMs for a total of 2 GB.

Run Prefs/UBoot, click the "Hardware" tab and at the bottom of the window, make sure that "Limit memory size reported to OS" is not ticked, or that the "Limit, MBytes" is the right size for your 1 GB RAM.

Remember to Save the new setting and do a cold reboot from the Reset button. If you still have problems after that, then it might be worthwhile to drop the memory bus speed from 133 to 100 MHz and try again.

I have 1GB of ram on my A1 (2 back of 512MB) and i have no problems at all.
Maybe the problem could be the type of RAM you are using... Not all ram bank are accepted well from UBoot..

@Atheist

Sorry if i'm not that much of a help here, i can only advise
you to drop the RAM (if you can give it back easily, do so) and
go for another one: two of these do very well for over 7 month here now.

About the technicals details...you got me, i just don't know anthing
about it.

About UBoot picky with RAM modules, i thnk it was/is a problem of the
hardware. If i'm not completely mistaken Mr. Frieden said it could
possibly be fixed, but he did not touch this part of the code for a long
time and it is also not planned to do so in the near future(?)

It would take time as it did with the Micro onboard sound...

So, my advice would be and i go here with afxgroup, drop the
RAM as it makes a lot of problems and get RAM that is known to work.

Sorry for the lack of help :-/

I'm using an AmigaOne XE G4 @ 800 MHz. AOS4.0 Pre-release 4.

The ram slots run left right when the MB is in front of me, in a desktop case.

I have a 1 Gig ECC Reg sdram in the far slot, and 512 Meg ECC Reg sdram in the close slot.

I copied songs off a CD into ram, and when it crosses 512 Megs, the system locks up.

In the BIOS, I selected (use this one time only) for booting up, and selected 1.5 Gigs of ram.

It KNOWS there is 1.5 Gigs of ram IN THERE (it sees it, allows me to increment the counter out to it), but can't use it.


Like I said before, I think it writes starting at address ZERO when it gets to ram address 512 Megs +1.


Also, does AOS4 Pre4 have virtual memory? I know that virtual memory = 2 Gigs - available ram.

IF it is trying to use 1.5 Gigs of virtual memory AND I'm using 1.5 Gigs of REAL memory maybe there is a conflict?

How can I set it, and/or turn it off?

@Atheist

Firstly, I think you'll find the RAM must be matched, so a 1Gb stick and a 512MB stick simply won't work.

Secondly, I really think you ought to update to OS4Final, there was problems with ram_handler (I think) which showed this exact behaviour, although whether it made it out to the public or not I don't know.

You are using a beta release of the OS, and as such I think your experiences may be sidetracked by this fact.

Update, and match the ram, then try it.

Simon