A3000T - memory issue?

[Tumbleweed]

Hi all,

After getting my A3000T running again its been working fine for a few months and then I started getting random "recoverable alerts" just after WB screen appears and when I open certain apps - iBrowse. Was an annoyance and I thought it might be software related. I did a clean install of OS3.2 and it seemed to be ok until a couple of days ago when the 3000T started suffering recoverable alerts and this morning critical failures (screen shot below) before booting WB and got stuck in an reboot cycle. 

The guru I think is telling me a problem with memory - chip mem?

I have run a couple of different memtests (memcheck and ziptest from aminet) and all show ok but maybe these are giving me false positives as the machine has booted fine prior to these being run.

My plan is to remove the Zip ram but want to avoid pulling all of the chips as they are fragile and I want to avoid bent pins or worse broken pins. Before doing so is there anything else I can check in software to identify a problem with the memory?

Weed

[Tumbleweed]

Thanks both.

I've a CSMKII with 128MB maybe its a dodgy SIMM or one has come loose. Ill check and reseat them later today. The RAM test I ran overnight with no issues. I'll leave the machine off for a few hours and then re-run overnight again. The issues seemed to be when I booted up from cold. Once booted it seems to be much more stable.

Best.

Weed

[Tumbleweed]

Left it off for a few hrs. Switch on - same issue red guru as before, followed by a reboot loop. Switched off. Removed the 5 1/4 drive cage and re-seated the SIMMs on the CSMKII. Switch on and booted off floppy into Amiga Test Kit. Removed floppy rebooted fine off the SCSI2SD.

Will run more tests - maybe an ill-seated SIMM?

Weed

[Tumbleweed]

All looked ok until I refitted the drive cage. I got a recoverable alert when starting iBrowse. Switched off. Removed drive cage and then removed the ram from the CSMKII. Switch on - no boot - black screen.

I then removed all boards - RTG, Network cards and the CSMKII. Switch on. No boot - black screen.

Removed 1MB of chip ram - the other 1 MB is soldered to the board. Switch on - boot and get the 3.2 boot screen.

If its a problem with the 1MB chip ram - that may be down to user error - I suspect I bent a pin when reinstalling it after the board was fixed. There is one ZIP with crumpled leg (its shorter than the others). Ill try straightening the leg, but if I need to replace the ZIPs - can you still get them easily?

Weed

[Tumbleweed]

Straightened the bent leg and refitted the ZIPs. Switch on - black screen. Removed all the chip mem ZIPs again switched on - black screen. I can here the drives clicking - floppy and the SCSI CD Rom is active - its almost as if its stuck in a reset loop. Monitor is flickering coinciding with the polling of the drives.

Caps lock key does not go off after more than a dozen pushes.

What's really odd is that after connecting the cables for the drive LEDs and the key lock, switching on, then off and then removing the cables for the LEDs its booting to the OS3.2 kickstart. Inserted floppy with Amiga Analyzer and can now run the memory tests. CHIP Ram test - 30+ rounds all ok.

With the me tests looking OK. I reinstalled the MKII - no memory installed on it. Switch on blackscreen. Soft reset a couple of times - no rainbow colours to show the CS as active. Then after switching off and a soft reset the CS rainbows appeared. Booted into Amiga Analyzer and now I can run the tests again. Could this be a PSU issue?

Installed the SIMMS in the CSMKII and now its in a continual reboot cycle.

Weed

[Tumbleweed]

Pat thanks for that. Th reset circuitry is not something I had thought about. The MB has been recapped and repaired. Was working fine after I rebuilt it until the last couple of weeks when I started to get the recoverable alerts and then the full software failure guru.

The initial symptoms were that it wouldnt boot straightaway - had to do a soft reset. Then I found I had to do more frequent soft resets to get it to boot from cold. The next thing I started to get was the red guru, and now its struggling to even boot - gets into this reset loop which it doesnt get out of.

The CS should be ok as I ran it in my A3000D and its works without any issues.

Edit: Just after posting I wiggled the CSMKII. Switched on and it booted straight into Amiga Anlayzer and everything looks ok. If I switch off and then switch on though Im not confident it will boot.

How can I test the reset circuitry? The issue seems to be when boot from cold, but once booted its mostly ok (maybe the odd recoverable alert though).

Weed

[Tumbleweed]

Could be Psu, could also be reset circuitry having issue on a cold start.

That Caps Lock light sticking on is odd, usually controlled by the keyboard controller inside the keyboard.

I think you might have more than one problem here. I would try powering on without the keyboard to see how far it gets.

EDIT: Using DeOxit on CPU and RAM connectors might help. The Cyberstorm (040 version) hasn't got much in the way of power smoothing capacitors, very much depends on everything else to behave.

I used this contact cleaner to clean the board before I rebuilt it. https://www.toolstation.com/wd-40-specialist-contact-cleaner/p87848 I also soaked the ZIPs in Isopropyl Alcohol before I fitted them. No harm in doing again though. Ill try the DeOxit this time.

EDIT: I ran AmigaMARK - Memory Benchmark and got this:

[Tumbleweed]

Thanks Pat. The CSMKII is supported with risers. The board is held in place with two screws.

Checking out the reset circuit is going to be a challenge as I dont have a logic probe, the schematics or knowledge on how to do it. The only chip mem on the board is the ZIPs soldered in place as I didnt refit the ones I removed from the sockets. Think my soldering skills are sufficient to remove / replace these though.

Its very odd though. When the machine starts it runs fine for hrs without any signs of memory problems. I can run the memory diags for hrs without any errors being reported. Checkmem, CheckmemHD, Ziptest, Amiga Analyzer all show no errors.

Edit: Booted fine first thing this morning. Went to change screen mode and got a recoverable alert.

from the error code looks to be:

0x0100000F   Recoverable   Memory header not allocated. Usually an invalid address passed to FreeMem()

So by the looks of it a memory issue or a memory controller issue - could that be a problem with Agnus?.

Thanks for your help.

Weed

[Tumbleweed]

Thanks PAT. Ive not serviced the PSU. its where I'll start looking.

I ran it all day today - running the memory diag from ATK v1.18. It generated an error screen shot attached. This doesnt mean an awful lot to me other than it looks to be an error on the 32 bit bus.

Any ideas as to how I should interpret it?

EDIT: And after a short time - chip ram = 0 Other mem = 4,160,555,704 (see screenshot of WB). I soft reboot and now its back into a reset loop after power off / on.

Best.

Weed

[Tumbleweed]

OK, that was definitely in the motherboard fast ZIP memory (07000000-07FFFFFF). Looks like a bad ZIP or maybe just loose.

What confuses me is only 1MB of chip RAM. Do you have half your chip RAM sockets empty?

I removed the socketed CHIP Mem ZIPS - thinking the problem was in chip mem. I didnt replace them. I have got the machine running mem diag on the fast ram using ATK (it booted fine after I left it off for a while). I will run overnight and see what happens. If it is the fastmem I will remove the fastmem ZIPs. Its apian as there are alot of them and its easy to damage them when removing and that maybe the source of the problem as I had removed them and refitted them after soaking in isopropyl alcohol - I did ben a few pins and it took me a few attempts to get them all seated properly.

I did some googling and reading past threads on A.Org and EAB. One suggestion was to check the tick signal from the PSU or switch the source using J350. I might give that a go tomorrow depending on the results of the ATK mem test.

Weed

[Tumbleweed]

I ran ATK overnight and it flagged a mem error in fast RAM as a I suspected it would. Slightly different error from the one flagged yesterday. So feels like FAST Ram is the issue. This kinda makes sense as I did bend pins when I installed the ZIPs and it took me a few attempts to fit them.

My plan is to remove the ZIPS one bank at a time and re-test using ATK.

PAT that is a very good suggestion re me mixing up the ZIPs. When I removed them I stored them in separate containers one for the Chip memory and the other for the FAST. They then sat for a long time (a few years) - maybe they got mixed up during that period but I'll double check.
 
EDIT: CHIP RAM ZIPs are all 256 modules. MB81C4256A-70PSZ 9250 D13Z is what is printed on them. Manufactured in Singapore.

I tracked down ZIPs from a UK seller on eBay last night and ordered 8 ZIPs. These look to be the static column type I think going by the spec - 258 as opposed to 256 which I read signals that they are static column.

TC514258AZ-80,TC514258 20PIN ZIP, 256K x 4 1M DRAM

Thanks for your help Pat I really appreciate it and I feel as though I am now getting somewhere. 

Weed 

[Tumbleweed]

Update:

I removed the Fast Ram ZIPs - ended up taking them all out as I discovered that I had bent quite a few pins when I had fitted them (see PIC). These are some of the better ones.

No will rebuild one bank at a time and see if I can correct the bent pins. If I cant salvage them I'll end up with less on board Fast Ram. Not a prob as there is 128MB on the CSMKII and on a positive note I now have an excuse to get one of these https://icomp.de/shop-icomp/en/produkt-details/product/bigramplus.html

EDIT: Fitted the Chip mem ZIPs - booted. Got the kickstart screen. Ran ATK - 2MB Chip found. Ran the mem diag - all good after 40+ rounds. Switch off. Populated Bank 0 with Fast Mem ZIPs. Switch on - no boot. Black screen. Soft reset - black screen. Switch off/on - black screen. Reinstalled CSMKII - switch on  Rainbow bars but then black screen. CSMKII is working as I get the rainbow when I soft reset but then it progresses no further. I get a black screen.

Removed chip ram ZIPs - boots. Up and running. Run ATK - 1MB memory found (correct all ZIPs removed and no CSMKII). Run mem test all looks ok.

Fitting the ZIPs into bank 0 seemed to trigger the problem. Its all very odd. Will try adding the chip mem ZIPS with the CSMKII and not populate the FAST ram.

Weed

[Tumbleweed]

ZIPs are areal pain as Castellen pointed out:

"Just to state the obvious, always double check the ZIP polarities before inserting them, check the pins are all aligned, and check pins are *between* the socket contact pairs before pressing them in place.  As opposed to employing a mutant gorilla with a sledge hammer as many people seem to do when fitting ZIP memory....."

the pins are so fragile and even when taking care its easy to bend them. For the 3000T the CHIP mem ZIPs arent too bad as you can get easy access to them. The FAST mem ones though are best populated with the board outside the case as the second bank is close to the floppy drive and CD compartments.

The ZIP to SIMM adapters are a neat solution but they are hard to find and for some they get in the way of the CPU card. I came across the link to the PCBWay website. I might have a go at that - need to get a decent soldering station though. Would make a neat mini project.

After a lot of testing various combinations of CHIP ram 1MB, 2MB CPU CARD no FAST Mem Zips etc and testing with ATK I have it booting happily into WB with no on-board FAST mem but with 2MB CHIP and 128MB on the CSMKII.

Will let it run overnight with ATK as before and fingers crossed no errors flagging when I look at it in the morning. 

I also tracked down some ZIPs for the FAST mem on eBay - almost the same as the original ones but slightly slower 80ns vs 60ns. The CHIP zips are 70ns. Does it make a difference that the CHIP and FAST operate at different speeds?

Weed.

[Tumbleweed]

Thanks Pat. I didnt know such a thing existed. Ill try it out tomorrow depending on how the mem tests go over night.

Very much appreciated.

Weed

[Tumbleweed]

Cheers Castellen. I ran ATK overnight. 3000T configured as follows:

1. CHIP mem populated with 2MB. I reinstalled the ZIPs I removed.
2. CSMKII 060 with 128MB SIMMS
3. No on-board FAST mem

Ran the all memory diag. No issues reported after 50+ rounds. Yesterday ATK reported errors in FAST mem with on-board FAST ram ZIPs populated. No probs reported today. I suspect I damaged the ZIPs / sockets when reinstalling them. I have new ZIPs arriving at end of this week. So may try them. I also have a 3000D so I can use that to test the ZIPs I removed from the A3000T.

Ill have a look at the PSU. I dont have a scope though but can check voltages using my multi-meter. Maybe I should recap the PSU. Not sure how onerous a task that would be but I am ok using a soldering iron so long as I am clear on whats to be removed and replaced.

Best.

Weed