My A1 with OS4PR run perfectly with one 512 MB RAM module, but when inserting the second one the computer hangs after the "Loading done, now launching kickstart" message. The output from the serialport is as follows:

U-Boot 1.0.0 (Apr 12 2004 - 14:05:39), Build: 04/12/04

CPU: MPC7455 v2.1 @ 933.333 MHz
Board: AmigaOne
DRAM: 1024 MB
FLASH: 0 kB
VGA: OK
In: serial
Out: serial
Err: serial
[libInit] returning 0x01AF1AB8
graphicsppc: ClearEOL()
graphicsppc: ClearScreen()

* * * Snipped lots of similar lines * * *

graphicsppc: SetOutlinePen()
graphicsppc: SetRGB32CM()
graphicsppc: ScrollRasterBF()
graphicsppc: SetRPAttrsA()
graphicsppc: GetRPAttrsA()
[SetupInterrupts] which = 1, intNum = 28 , IRQ = 12
[SetupInterrupts] which = 0, intNum = 17 , IRQ = 1
68k LINE F EMULATION: PC=0x0000000C, opcode=FF7F
0000000C: UNKNOWN COPROC OPCODE
0000000E: moveq #-0x21,d7
00000010: moveq #0x75,d7
00000012: subq.w #0x7,(a5)
00000014: cmpa.l ([-0x1451,zpc,a3.l*2],-0x6),sp
ThisTask: 0x01AED878
68k register dump:
DATA: 01AF2457 01AF2412 00000000 00000000 00000000 00000000 00000000 00000000
ADDR: 01AF2412 01AF92E0 00000000 00000000 00000000 00000000 00000000 01A14AAC
STCK: 00000000 01A14C70 018231B4 4EB9FFFF FFE24EF8 00000001 01823280 02013C03
Dump of context at 0x01AE1150
Trap type: Program exception
Machine State (raw): 0x0002F030
Machine State (verbose): [ExtInt on] [User] [FPU on] [IAT on] [DAT on]
Instruction pointer: 0x0180D35C
Crashed task: exec.task (0x01AED878)
0: 0183324C 01A14A70 25050750 8000000B FE0003F8 00000040 01A30000 00000000
8: 01A14A00 01A03E4A 00000003 01A14A60 24024028 00000000 01AEDA88 00000001
16: 00000000 01AEDA8C 00000000 00002457 52057050 0000000E 01AEDAA8 00000010
24: 00000000 0183BA80 00000008 01A14D08 10040430 0000000C 01A359E4 0183ADF0
CR: 24024024 XER: 20000000 CTR: 00000000 LR: 0181AD78
Program exception verbose description:
Trap instruction
IP points to excepting instruction
[libInit] returning 0x01AF1AB8
graphicsppc: ClearEOL()
graphicsppc: ClearScreen()
graphicsppc: SetFont()
graphicsppc

From here it seems to loop. Both my memory modules are Kingston KVR133X72RC3L/512 and both works perfectly with only one inserted. Any ideas?

_________________
Vidar

NOT a self-appointed internet police..

@Vidar

Any ideas? No.

Simply go to the nearets friend's home and stole 2 pc133 dimms to try on your A1 -) So if you want to see if the problem are the ram modules this is the solution

_________________
ikir

@Vidar

Gday i have 2 X 512mb sticks in my A1 XE G4 they are both redgestered and self error checking i have no probs with them at all
Are you using redg - ram ?

@poweramiga2002

Are you using the Legend branded memory?

@Bodie

No, it is Infineon. Both modules are delivered from Eyetech togehter with my A1. As I tried to say, both modules works perfectly OK alone, but not the two together. As far as I know they should be registered, but I'm not quite shure how to determine that..

_________________
Vidar

NOT a self-appointed internet police..

@Vidar

As I recall from the a1g3dev list, the AmigaOne is very picky about ram. In order to use two modules, it must be registered, and only certain specimens of certain brands work. I'm pretty sure your part number is the same as mine, so yours are registered; that's not the trouble.

Kingston ValueRam made with Infineon chips USUALLY works in pairs, and Kingston ValueRam made with Mitsubishi chips usually does not work in pairs. However, if the Mitsubishi chips were made in Taiwan, they work (I can verify this directly, because that's what I've got and both modules work together under Linux), but those made elsewhere do not.

I suspect that most Kingston ValueRam with Infineon chips will work, and some not, based on where the chips were made. At the time the A1s were shipping, dealers had to decide what chips to ship with the systems, and the only memory that seemed to consistently work was Kingston with Infineon and the Legend brand (shipped mostly by Australian dealers).

If I recall correctly, Eyetech even went so far as to negotiate with Kingston to purchase a stock of ValueRam with Infineon chips only (no Mitsubishi). This was somewhat above and beyond their duty, in my opinion, since normally you just order hardware by part number. Kingston was quite helpful; even though they don't keep the Infineon memory separate from the Mitsubishi memory in their inventory, they hand-sorted some out.

if it is true that it makes a difference where the chips were made (i.e. if the Amiga One memory controller is so extremely picky that manufacturing variations from one plant to another make a difference) then you will need to get a good magnifying glass out and try to read the markings on the ram chips to see if there is any notation saying where it was made. Then you can ask someone who has known working Infineon-based memory to please look at their chips to see where they were made. If it's different, they you can try to get someone to swap your ram for some that has the exact working type of chip on it. I know this sounds like a lot of work and a log of if's, but at this point, I can't think of anything else for you to try.

--Stuart Anderson

@Bodie

Quote:

Bodie wrote: @poweramiga2002 Are you using the Legend branded memory?

No they are micro technologies ram modules

They also work as 1 gig memory in linux boots no probs

@mr_homm

I would still like to see (and you'd have to be a dealer or supplier for this) a proper statistical survey of different motherboards/DIMMs/etc in combination. I'm sure we'd find that a pair of Ajax brand DIMMs will work fine in Fred's motherboard but won't in Clare's, and so on. The results at present are just too inconsistent.

The number of A1s (and DIMMS of different brands) in any one place is too small to do it at the moment.

tony

_________________
cheers
tony

Hyperion Support Forum: http://forum.hyperion-entertainment.biz/index.php

@tonyw

I agree. Since minor variations (within manufacturing tolerances) seem to matter, then whether the memory works is essentially random, once you've narrowed it down to one of the "probably working" types. it would be nice to know whether there is one particular factory/production run that ALWAYS works.

The time to find that out, however, was when all the boards were together in one place, at the fabrication plant or at Eyetech. Of course back then, it wasn't known that the memory controller was this finicky. Everyone thought the problem was solved by choosing Legend or Kingston/Infineon.

By the way, I purchased my memory long before the A1-XE G4 was even manufactured, based on early information gathered from the A1-SE G3. In hindsight, this was a stupid thing to do, but just by blind luck, I happened to buy a pair of modules that have worked flawlessly. Oh well, I suppose someone has to take the risks of trying out hardware for a new board; I'm just glad it worked out.

Stuart Anderson

@tonyw
Quote:

I would still like to see (and you'd have to be a dealer or supplier for this) a proper statistical survey of different motherboards/DIMMs/etc in combination.

Mr. Hardware (Russ Norrby) has already solved this problem. Russ partnered with a RAM manufacturer, invested, solved the compatibility problems and sells RAM that will work 100% in your A1 including 2x512MB sticks--for a premium of course.

To date, only Russ has claimed to have found and solved the real technical problems with A1 RAM compatibility. Everyone else just seems to make a good guess and hope for the best (e.g. the Kingston RAM recommendation by Eyetech).

_________________
ExecSG Team Lead

@ssolie

I don't have two of them, but I have a single stick of registered PC133 RAM from Crucial (all their chips are made by Micron) that works fine so far with Linux (still waiting on OS4 Pre to arrive). It's 512 MB.

Sure wish I had another one to try (couldn't afford to buy two of them at the time), but that's luck I guess. As it is I can't justify buying another one because if it doesn't work, then I would not be able to use it in the only other board I still have that uses SDRAM (that board is old enough it only supports up to 256 MB per slot, and even those have to be particular types).

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This posting, in it's entirety, is the opinion and/or statement of the author and does not reflect the views and/or position of this site.

@DWolfman

I have mentioned this a thousand times before KINGSTON DOES NOT MAKE SDRAM.
thier part numbers are meaningless. Thier tech support is worthless and trying to get someone there that knows anything about memory is almost impossible.

The problem Russ has is like most Amiga dealers can't afford to lay out a huge sum of money to have a large quantity of SDRAM made. small batches results in a higher price but his SDRAM does work. I am currently out of his MRHC memory but it does work in any combo meaning his 128 can be mixed with 512 or his 1 gig sticks. He had a special for the last couple of months on 1 gig sticks for $350

The only problem is Linux barfs with more than 768 megs of total memory so if you run linux you have to use the limit memory arg in uboot.

good news is two Gigs of RAM and OS 4 does not use any virtual memory.

My suggestion is to buy your PC133 RAM now prices have doubled in the last year and they will only go up!! As people migrate from PC133 prices will continue to rise for new pieces.

Russ has 128,256,512, and One gig sticks.
lifetime warranty

kgrach