SE/30 with fx ROM & no PRAM battery

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Von
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I saw a post on 68kmla (before it went down) regarding an SE/30 with fx ROM installed not getting this garbled screen at boot up if the PRAM battery was removed:

003 was that your post? DId the issue return when the battery was replaced?

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003
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Joined: Jan 19 2007
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Yes that was my post, and yes

Yes that was my post, and yes the issue comes back when you replace the pram battery. I can not do any testing on my SE/30 right now because all my logic boards for it are out of commission, and need to have the capacitors replaced/resoldered

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JDW
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Battery irrelevant?

I recently replaced a dead battery in my SE/30, which exhibits that same exact screen garbage at startup. The new battery is definitely good, and I confirmed that with a DMM (using the same DMM I confirmed the dead battery was indeed dead). But even with the good battery, I still get the screen artifacts on startup. My computer cold boots to those artifacts and stays that way for more than a minute, until the RAM checks conclude (it takes so long on my SE/30 because I have 128MB of RAM).

If memory serves me correctly though, I still got the artifacts even without any battery on the logic board at all. But to prove if my memory is correct, I will need to break down my machine, remove the battery and test again. No time for that today. But I will report back when I do that test.

Von
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Tech Tool // Zap the Parameter

I found this in the help file of Tech Tool 1.07:

Zap the Parameter Ram:
The parameter RAM (PRAM) contains user-definable settings that must be retained after the computer has been deactivated. Settings such as time of day, mouse scaling, keyboard repeat rate, and startup drive preferences are all stored in the upper 64 bytes of PRAM. Traditionally, one could clear or "zap" these upper 64 bytes of PRAM by holding a special key combination at startup or before selecting the control panel. This often cured behavioral anomalies which could not be remedied with software replacement.

Below the standard 64 bytes of PRAM lies another 192 bytes of memory which are, for the most part, publicly undocumented. These are secret storage areas that Apple uses for such things as Manufacture Date and Factory Service settings. When these portions of the PRAM become corrupted with invalid data, odd problems can occur and sometimes the machine will fail to work at all. Traditional PRAM zapping does not clear the lower 192 bytes of PRAM. The only alternative is to remove the PRAM battery, which is often soldered to the logic board. TechTool clears all 256 bytes* of PRAM memory without the need to remove the battery. Once the system is rebooted, the Macintosh ROM will replace the PRAM contents with its default or factory settings.

Usage:

  • Push the Zap PRAM button.
  • You'll be prompted to SAVE the PRAM data before zapping it.
  • If any applications are running (besides TechTool and the Finder) you'll be prompted to quit those other applications.
  • TechTool will prompt with the message, "Are you sure you want to zap the parameter RAM?"
  • If you select "YES", TechTool will set all PRAM bytes to 0 and then force the system to restart (the system doesn't like having active PRAM data tweaked).
  • The system will boot again, restore the mandate and then restart again. (see Manufacture Date section for explanation)
  • Factory default settings will be restored on the next restart.

I am wondering if perhaps using this tool could clear up the garbage at startup one gets if running an fx or si ROM in a SE/30. Any thoughts?

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JDW
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PRAM Zapping & Battery Removal Impact on Artifacts

Von & 003,

I made time tonight to break down my machine to conduction the following tests:

1) Removed PRAM battery and did a cold boot. Even with battery removed, the artifacts show at startup during the entire time the RAM is being checked. The machine then boots normally.

2) I restarted with the PRAM battery still removed and this time held down the CMD-OPT-P-R keys to zap the PRAM. Upon holding down those keys at boot time, I hear a second boot chime and the screen refreshes itself as if it were rebooting. I then booted to the Finder, shutdown the machine, waited a couple minutes for contents of RAM to clear, then did a cold boot. Artifacts still show up in the same manner as I reported in (1) above.

3) I repeated the process of Step (2) but using TechTool Pro 2.5.1 instead of CMD-OPT-P-R at startup (to ZAP the PRAM). The battery was still removed when I did this. When you zap PRAM with TechTool you are forced to restart. After this restart, I then shutdown the machine and waited a couple minutes for the RAM to clear. But upon cold boot, the artifacts still appear.

4) I yanked the logic board at this stage and re-inserted the battery. Yes, the battery is good. I know this not only from checking the battery voltage in-circuit and out of circuit, but also by actual testing -- I had the battery in the logic board for over a week with the machine disconnected from wall power and the date and time remained accurate during this time. Cold-booting in this condition (with the PRAM battery now inserted into the logic board) results in the artifacts, just like all my previous tests. I then rebooted with CMD-Opt-P-R held down, but the artifacts remain on reboot. I then used TechTool's PRAM zap, but the artifacts remain. (And yes, I ran all the PRAM tests except the "Major March" and all tests passed.)

So it is clear from my exhaustive testing of PRAM zapping, both with and without a known good PRAM battery inserted in the logic board, that PRAM has NOTHING WHATSOEVER to do with this artifact-on-startup problem. And as I have reported elsewhere, all my motherboard caps have been replaced with a combination of tantalum caps and electrolytics, proving these cold-boot artifacts cannot be SimasiMac.

Any other thoughts at this point would certainly be appreciated. Even so, like I have mentioned before, the artifacts are "worrying" but they appear to do no harm. I have not noticed any problem with my machine so far, even with PDS cards inserted.

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I have had this probelm as we

I have had this probelm as well when replacing the SE/30 ROM with a ROM from a IIsi. Sometimes it worked and sometimes the screen looked exactly like your picture. Does the problem go away if you restore the original SE/30 ROM (it should)?

The only other thing that might help is to carefully remove and re-seat all of the memory and the ROM.

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JDW
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Those things do not help

Microns, thank you for your reply. (I was beginning to think this thread was about dead!)

The artifacts remain even with the stock ROM. And when I say I have tested "the stock ROM," you can believe me! I have 3 different (hardwarewise) SE/30 ROMs, and the artifacts show up when any of them are used. So these proves the ROM is irrelevant in my case.

I have reseated RAM more than anything else. I've tried various combinations of RAM, from 1MB SIMMs all the way to 16MB SIMMs. RAM configurations and reseating doesn't fix it.

Of course, I would certainly appreciate any further insight some of your hardware experts out there might have to share!

Von
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Artifacts only with IIfx ROM

JDW wrote:

The artifacts remain even with the stock ROM.

Interesting...I didn't have the artifacts until I inserted a IIfx ROM. When I replace the IIfx ROM with the stock SE/30 ROM the artifacts are gone. FWIW, my system has 80MB of RAM (4*16 + 4*4).

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JDW
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IIfx ROM

Von, thanks for the reply.

I once had another working logic board (now dead) which never had the screen artifact problem (as shown in the photo at the start of this thread). When I used the IIfx ROM in that machine, there were horizontal lines at cold boot and they remained on screen until the RAM tests completed, then the normal happy Mac icon and boot sequence appeared. On my current logic board, the horizontal lines do not appear because the screen "artifacts" (shown in the photo above) appear instead. But in the case of my other logic board, I only got the horizontal lines with the IIfx ROM, not with IIsi ROMs or any other ROM; whereas I get the screen artifacts on my current logic board regardless of ROM.

Also note that although the horizontal lines with the IIfx ROM look exactly like SimasiMac lines, the lines are not related to SimasiMac when you have a IIfx ROM inserted in your machine. I certainly would like to know WHY you see horizontal lines with the IIfx and Simasi Mac, but I guess no one is technosavvy enough to know that. (Yes, I know some will be quick to point out that "bad capacitors" result in the Simasimac lines, but I want to know the DEEPER reason WHY -- in other words, why not vertical lines or diagonal lines or something else instead. But then, I am also searching for the technical reason why these odd screen artifacts appear too!)

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tt
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Other screen artifacts

I get this artifact with one motherboard I have with an Xceed Color30 and IIfx ROM. Has anyone else seen this effect?

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logic board

Yes, I have the exact same problem on My SE/30 with 20mb ram. After a few restarts, it works fine. I think it has something to do with the logic board needing a cleaning and/or capacitor replacement.

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JDW
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Re: logic board

macintosh wrote:

...has something to do with the logic board needing a cleaning and/or capacitor replacement.

Cleaning? Yes.
Cap replacement? Unlikely.
Read the information presented at the following two URLs:
http://www.biwa.ne.jp/~shamada/fullmac/repairEng.html#CheckerFlag
http://macfaq.org/hardware/graphics.shtml

I verified the information presented on those two sites parallels what is written on page 175 of Larry Pina's "The Dead Mac Scrolls." It therefore does NOT appear to have anything to do with capacitors on the logic board (as it is with SimasiMac).

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tt
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Yes, I have seen it before wh

Yes, I have seen it before when the ROM was loose, but in that case the system hang was permanent. In this case goes the artifact goes away after a few seconds. On a quick on-of sequence at the checkered patterm, the artifact will change as if some of the graphics information from the prior startup is retained.

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JDW
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Try this

tt, I follow you, but it still could be variant of the same problem.

Please click the second link I provided for you above (in my previous post). Now scroll down to the header, "2.1.4 - How can I fix my Compact Mac's video problem?" Note the part about the possible need to resolder certain points on the analog board. I strongly advise that you try this. It very well could cure your problem even when reseating the SE/30 ROM didn't.

By the way, is the startup "bong" sound muted or choppy? Or do you hear that boot chime just fine when you switch on your SE/30?

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JDW
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Not such a rare problem after all

I see that the "strange artifacts" problem exists even on SE/30's currently being sold on EBAY. These artifacts are EXACTLY like mine, to the pixel. (Also note this AppleFritter thread and this 68kMLA thread talks extensively about these "strange artifacts.")

In light of all the well known CRT patterns documented by Larry Pina and others -- screen patterns that are always the same when hardware exhibits certain problems -- there absolutely MUST be a technical reason for the "strange artifacts." Surprisingly, neither Pina nor anyone else on the web has ever documented the hardware reasons for the "strange artifacts."

Everyone continues to tell me "don't worry about it" as a means to avoid saying "I don't know what causes them." But I want to know! What in the world causes these "strange artifacts." And with Larry Pina having put such a comprehensive list of classic Mac CRT screen patterns in his books, why aren't the "strange patterns" in his books? I can only guess it is due to something that has taken 20 years to surface, which is something that Larry Pina would not have seen during the time his books are written. A real mystery, to be sure! And one I wish to solve!

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my guess would have to be a r

my guess would have to be a rom incompatibility with the se/30

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JDW
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It is NOT the ROM nor ROM contacts, folks!

gobabushka, the ROM has been suggested to me before, which is why I provide links in my above posts to other discussions on this where I state quite clearly that it is not the ROM nor the ROM contacts. Someone else who didn't want to read through the links I provided posted the same exact question today on 68kMLA.

I have two working SE/30 stock ROMs and the strange artifacts appear regardless of ROM and regardless of the fact my ROM contacts are clean. It is not the ROM. It is not the contacts to the ROM. It is something else, which is why I have posted this again in hopes of attracting further technical speculation as to why it is likely occurring (for reasons OTHER than the ROM).