A3000T 16MB Fast + RAM on CPU card probs

[TjLaZer]

OK I recall there is an issue with A3000(T) computers with MB RAM and RAM on CPU cards, anyone have this issue?

I just got  my A3000T running by installing a replacement MB, it works fine.  It has 16MB Fast on MB, I install my CSMKII 060 card with 64MB and I noticed once RAM is used up (and MB RAM is not starting to be used) it starts to crash.  Any other 3K users have this problem?

-edit-

seems there are issues with CSMKII cards and A3000's!

[gdanko]

Never seen such a problem!

[Zac67]

TjLaZer wrote:
I noticed once RAM is used up (and MB RAM is not starting to be used) it starts to crash.

Once which RAM is used up? Accelerator RAM should have higher priority and be used first. Maybe your MB RAM is just defective - try to test it with the CS in place and without. If the former doesn't work but the latter does, then there's a problem with the CS.

[CLS2086]

Please tell us, what is your OS,startup seq, patchs....

[TjLaZer]

Look at the included link to Google.  Seems some boards, the Cyberstorm MK II 060 in my case, has issues with the onboard MB RAM.  Causes crashes, glitches, etc.  Especially once the Turbo RAM is used up, and you start to enter the slower MB RAM!  I test this by copying large data until all my card RAM is gone.  ie I have 64MB, and 16MB MB RAM, I copied ~64MB of data into RAM: thus forcing system to start using the slower MB RAM, then crash.

I have OS 3.9, 4GB SCSI HD, latest chips.  I did find another article that someone stated he reverted to old Ramsey/Dmac and problems went away!  Hmmmm....

[Zac67]

Hmm, the accelerator shouldn't have problems with MB RAM...

You got static column or fast page? If it's SC, maybe Ramsey is trying to burst and that fails. If you replace the first 4 MB bank with FP, burst mode will be disabled. (I'd be happy to swap 4 MB FP for SC... ;-)) It should even be possible to fiddle with Ramsey's registers and deactivate burst with a tiny tool. I wrote something like that (for the bus timeout option) wayyy back, dunno if I can still find it.

If you don't want to use any software method (requires a little something to be executed after boot), just pull one chip of the first bank and the rest will be ignored.

TjLaZer wrote:
OK I recall there is an issue with A3000(T) computers with MB RAM and RAM on CPU cards, anyone have this issue?

I just got  my A3000T running by installing a replacement MB, it works fine.  It has 16MB Fast on MB, I install my CSMKII 060 card with 64MB and I noticed once RAM is used up (and MB RAM is not starting to be used) it starts to crash.  Any other 3K users have this problem?

-edit-

seems there are issues with CSMKII cards and A3000's!

Yes, because of this problem, my A3000 PP&S Mercury came with a specially modified ZIP RAM chip that was intended to replace the very first ZIP chip on the MoBo.

This problem seems to occur only when you have Static Column DRAM (514402) type of memory. It should not occur when you have fast page mode DRAM (514400) type of memory.

Your problem seems to be caused by a bug in RAMSEY.

[TjLaZer]

I have 3 different types of ZIPs installed, all random.  How can I tell what kind each is?  Also where is the beginning of each bank layout?  I will try that method.

[Zac67]

Actually it's more a bug of the CPU card - they shouldn't try to initialize a burst transfer if they can't manage to do so.

Ramsey can only do '030 bursts which (I was told) are totally different from '040 bursts... Using a fast page ZIP in the first bank will disable burst mode completely and (if that is the cause) will solve the problem.

Followup: found some of my old notes - the Ramsey register in question is $DE0003:
Bit 0: page mode
Bit 1: burst mode
Bit 2: burst wrapping
Bit 3: RAM size (0=1M, 1=4M)
Bit 4: RAM width (0=1 bit, 1=4 bit) //whoah - never knew 1 bit was possible...
Bits 5-6: refresh rate
link

So all you have to do is to turn off bit 1 (you might have to be in supervisor mode to access Ramsey) and that'll disable burst mode with SC RAMs - voilá.  ;-)

[Zac67]

SC chips end in ..02, FP in ..00. If your first bank is SC and the rest mixed - well, that ain't good for stability...
A mixed setup in the first bank should disable burst mode, but I'm not sure what exact method the ROM uses for detection...

[TjLaZer]

I read some old info on usenet about reverting to old DMAC and Ramsey revisions!  What should I do?

[Zac67]

There are couple of tools on Aminet that you should try first.

[T3000]

TjLaZer wrote:
What should I do?

Remove and forget the 16 megs of mobo ram. The toaster system won't miss it.

I had tried (long time ago) putting a WARP'40 in the A3000T. Worked good without ram on the warp card. Once the warp ram was installed, the system got flakey. I then removed the ram from the mobo. Worked fine.

[TjLaZer]

Well not sure what I did, but it seems to be working ok now!  I reverted to another HD install I had from last year and it seems to be working ok.  I have 128MB on the MKII now and I did the test. Filled up RAM: so there is only MB RAM left (like 7MB free RAM) and saw it system was stable or not.  Seems ok now for the past few days!