I've got a turbo cube with a Dimension board I'm trying to revive. The
unit was working a couple of years ago and has been in storage. The
CPU board boots 3.3 from the hard drive with no problem. I've swapped
Dimension boards with a loaner and it works fine in my cube. My
Dimension board will not initialize a monitor (monitor stays in
powersave mode). I've ruled out bad SIMMS.
I've downloaded the dimension diag tools. Here are the results from a
couple of the utilities:
- NDromcopy - erases and rewrites the ROM succesfully.
- NDromload_BI_DramAndVram - erases and rewrites the ROM
- NDromcheck - returns successfully with a checksum
- NDprocmem - Fails with something like "i860 would not stop
- NDinfo - Fails with "failure(5)"
- NDgamma - When I use this command my monitor comes out of
powersave (blank screen).
- NDcbars - I get a faint color bar pattern (kind of grainy).
If I keep using NDgamma 4 or 5 more times, it keeps increasing the
gamma and ultimatley I get a nice bright color band on the monitor.
Maybe this is directly tickling the Bt848 chip?
I know its a long shot if a component has failed on the board. My best
bet I guess is if I can narrow it down to one of the major chips
failing. Then at least I might have a shot at replacing it...like
maybe the NBIC chip or the i860. Just not seeing enough from the diag
utilities to get any comfort on what it might be.
Any ideas help, encouragement, test proceedures, anything
Thanks to anyone left reading this board!
DId you use the same cable on both NDs? When you boot with the "bad"
ND, does the CPU board try to put the console there?
The reason I ask is that NDs detect the presence or absence of a monitor
by measuring the capacitance on the cable. It's possible, although I
admit unlikely, that your cable/monitor combination is fouling this
somehow. I know this isn't too helpful, but it's a thought.
I found a really old USENET post that listed the error codes for the
LED on cube and slab motherboards. If you recall, my Dimension board
was flashing 5 times then repeating. A sequence of 5 on a motherboard
means "No DRAM found". So, on a hunch that the NeXT engineers tried to
keep things consistent with the Dimension board, I rechecked the DIMMS.
One was bad. I checked them before, and even watched Rob over at
BlackHole Inc. check them over a year ago. Guess we both screwed up.
My Dimension system is back up and running!
So for the sake of future seekers of Dimension board knowledge:
A sequence of 5 blinks on the board means Check the DIMMS.
> I found a really old USENET post that listed the error codes for the
> LED on cube and slab motherboards.
I'm really interested to read this old post: I have two slab (one mono
and one color) that blinks some times, no video signal on monitor.
Can you re-post the "old post" just so that it makes it to the
Five flashes in a row on the magic EKG LED indicates that the ROM
memory probe didn't find any (usable) DRAM. The ROM code is testing
the first 8 Kbytes of each bank of memory looking for a place to put
the ROM stack. In your case, it didn't find any. I'd examine the DRAM
sockets VERY carefully for broken/bent tines, and for cold solder or
flexure breakdowns. One pin not making contact is all it takes. Also
look arount the base of the memory controller (That big ole Fujitsu
chip on a 25 MHz machine). The freeze spray treatment Bruce mentioned
Just for fun, here are the EKG blinky light flash counts for assorted
1,2 ROM CRC check failures
3 Bad VRAM
4 Bad NVRAM (The NVRAM store in the clock chip)
5 No usable DRAM