Gerhard.Lenerz wrote:
zuluchas wrote:
Well, what I found was then when I put known perfectly good 8MB sticks in the MC2, they came up as 2MB! I tried it with 8x 8MB sticks, arranged in matching adjacent pairs, each set of four identical -- the 4D sees 16MB. I tried it with 12x 8MB and got "24MB." This is without any 2MB sticks in at all, so it has nothing to do with the supposed inability to mix 8MB and 2MB on the same board.
Is this a PROM version limitation, as suggested in the above post? Or am I missing something?
I finally had the chance to run a test with a 030-0117-001 MC2 board and as you describe, the 8MB SIMMs are not recognized. With 8 SIMMs installed the PROM reports 16MB and no error on startup. IRIX boots fine, for very low values of fine (5.3 isn't fun with only 16MB).
The other equipment in the system I used is rather new (IO3B and IP15). Given that it normally runs with a newer REV MC2 (8MB SIMMs installed) I presume it is safe to say that the limitation is related to the MC2 board itself.
Compared to the pictures I posted earlier the 003-0117-001 MC2 looks quite different. Most obvious is the lack of labels on most parts and a lot additional blue patch wires.
Thanks to Jan-Jaap, I have acquired a newer-rev MC2 board which *does* work with 8MB SIMMs:
1. (New MC2 + 128MB in left slot) + (nothing in right slot) = 128MB recognized
2. (Old MC2 + 24MB in left slot) + (nothing in right slot) = 24MB recognized
So far so good. HOWEVER...with both boards in the system I still can't access all the memory:
3. (New MC2 + 128MB in left slot) + (Old MC2 + 24MB in right slot) = 88MB recognized
4. (Old MC2 + 24MB in left slot) + (New MC2 + 128MB in right slot) = 24MB recognized
Case 3 is really bizarre: it seems that 24MB on the right board are all fine but only 4MB of each of the 8MB SIMMs on the left board are recognized. The appropriate number of green status LEDs are lit on the board edge for each card, so it's not like half the 8MB SIMMs are unused. So the board thinks the 8MB SIMMs are only 4MB when 4MB SIMMs aren't even supposed to be supported? Strange.
Anyway, 128MB is pretty nice with IRIX 3.3.2!