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Bad ROM in SE/30

I was finally putting my freshly recapped (thanks, uniserver!) SE/30 back together and got tight horizontal stripes on startup.  Thought it was RAM at first (which it wasn't) and after checking everything else I thought I'd swap the ROM SIMM from a machine I'm fixing up for a friend.  Voila, everything works great and my ROM SIMM in her machine produced the exact same effect, no boot and tight horizontal stripes.

How often do ROM SIMMs go bad?  I see several SE/30 ROM SIMMs on eBay, any advantage of one revision over another? 

 
Polish the edge connector on the ROM SIMM and try again.

Also - boot it without the ROM SIMM. The ROM SIMM only provides 32Bit Clean ROMs to the SE\30 if you got it from a IIfx. The SE\30 already has the older 24Bit ROMs on the logic board so it can boot up without the ROM SIMM. If your 24Bit ROMs work, your SE\30 should be fine. You can add the Mode32 Extension to your system folder to access more RAM.

Also check the ROM SIMM Connector and make sure its pins are clean.

 
Polish the edge connector on the ROM SIMM and try again.

Also - boot it without the ROM SIMM. The ROM SIMM only provides 32Bit Clean ROMs to the SE\30 if you got it from a IIfx. The SE\30 already has the older 24Bit ROMs on the logic board so it can boot up without the ROM SIMM. If your 24Bit ROMs work, your SE\30 should be fine. You can add the Mode32 Extension to your system folder to access more RAM.

Also check the ROM SIMM Connector and make sure its pins are clean.
Good to know, didn't realize I could boot it without the ROM SIMM (not that I had tried).  Already have Mode32 ready to go as well.

hey can you take a picture of the stripes, or are they thin lines?
I'll take a picture of it when I get home from the office this evening.

 
Good to know, didn't realize I could boot it without the ROM SIMM (not that I had tried).  Already have Mode32 ready to go as well.
That's funny, because Mode32 is not needed if you are using a ROM SIMM from, lets say, an IIfx. The ROM SIMMs are 32Bit Clean while the ROM on the logic board are 24Bit dirty. Mode32 is only needed for 24Bit Dirty ROMs.

My IIfx, IIsi and SE\30 does not have a ROM SIMM and all boot just fine without it. 

ROMs are hard to "Kill" but not impossible to kill. There are millions of dead video game cartridges out there that would attest to that. Look at the ROM SIMM with a magnifying glass and see if the solder joints and traces broke on the SIMM. I'm guessing that the ROMs are OK but a broken solder joint or trace is killing the SIMM. Putting some flux on the ROMs and Hot Airing them should fix it. At worse you may need to remove the ROM Chip, clean up the traces, check them with a multimeter, and solder the ROMs back on.

 
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The GALs and PALs make up the ROM for the SE\30.

I can attest that I have no ROM SIMM in my SE\30 and it does boot up system 7.5 without issues or problems.

 
The GALs and PALs make up the ROM for the SE\30.

I can attest that I have no ROM SIMM in my SE\30 and it does boot up system 7.5 without issues or problems.
 hahaha... thats funny...

the SE/30 requires a ROM SIMM unless you have some phantom unreleased board. 

 
I will concede in that you might be right, TechKnight.

I'm looking at my old dead SE\30 board and it has no ROM SIMM. The replacement board may have it, I do not ever remember a ROM SIMM being on that original board. Hence that may be the problem after all - the original dead board never had a ROM SIMM but the replacement does? I need to pull down the SE\30 off the shelf and open it. Can't right now - too tired to do so, so I will have to do so tomorrow.

 
didn't i see a prototype SE/30 board with 4 spots with portholes for rom's like what was used in the IICX?   haha  

 
There are two SE/30 ROM versions (that I've seen); neither will say "SE/30."  The one you posted is 820-0241-02 / 630-4339; the other is 341-0655A [i'm not clear on the consistency of those serials...].  You can also put other more exotic ROMs in there.  I would be surprised if they'd boot without ROMs, but now I'm curious.

EvilCapitalist (muwhaha) could you take a picture of the chip-side of the ROM from different angles, particularly the right-most chip?  I think I may see corrosion on/near a via on the underside that suggests perhaps corrosion on the right-most chip.  Also, have you tried to wash the ROM?

 
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it is that time of the year, maybe you zapped it.   I do have a rom here that is the same as that one that is tagged as flaky in my box.

 
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