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About GeekDot

  • Birthday 08/21/1970

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    Yurop - Go see the Queen
  • Interests
    If it beeps and/or blinks, I'm in!

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  1. GeekDot

    Quadra 950 PSU died... <cry>

    Thanks, glad if this is useful for somebody else! As for the todo-list: I need to "clean" the remainders first as I promised the parts to someone else who is on the mission to repair an old PS "the correct way" as @techknight would probably say Hopefully this is been done this week - suffering severe vintage-project-ADHD I got dragged into other realms of resurrection (http://www.geekdot.com/the-mips-rs2030/) and need to force myself to return to the good ol' Macs (not to mention the SE/30 vs. Carrera040 riddle still waiting to be solved).. 1) Well, there's certainly a higher efficiency with good, modern power supplies. This means it will waste less watts coming "from the wall" to feed you Quadra, i.e. saving $$$ That said, mine is a crappy, cheapo and example of bad engineering, so I doubt it's that much of a saver. OTOH lady Quadra is not running 24/7 so the impact is negligible. 2) Yes, you have to have the case open no matter if you're planning to replace the fan or keep the original one. This is because you have to somehow adapt & connect the new or old fan to the replacement PS. The noise level is of course related to the fan quality you choose. I picked an average one (~10€) which is much more silent than the original one. You can probably go some db lower by spending the double amount. Again, there's a nota-bene: The PSU fan ist the only fan for the whole system - a principle many vintage machines followed (read SUN/SGI and the like). Thus the fan had to pull the heat through the PSU while having enough juice to cool the PSU, too. So todays measure of "CFM" ( cubic feet per minute) isn't sufficient to choose the right fan for an original PSU: You have to make sure the static pressure (which tells us how good the fan is at sucking air over various objects at its intake) is within the specs of the computer manufacturer. Here's an example from the SGI-World: The EBM Papst 8412N running at 3100rpm has a CFM of ~40 and a static pressure of 4 while the often used & modern Arctic F8, delivering a nice CFM of 30 @ silent 2000rpm, has a static pressure of just 1. Not enough to cool the computer itself. It'll cook itself to death sooner or later. It's a bit like horsepower vs. torque with cars. Figureing out all these specs is quite hard today. Again, because you bravely swapped your Quadras PSU to a newer, modern one you don't have to care about this as these PSUs aren't getting that hot and an average PC fan is just fine - not sure how much this is true for a fully loaded Q950 with PPC accelerator and 4 hard-drives, though. P.S: A nice side-effect: My Q950 is much lighter now! You can really feel the difference when hauling the beast around...
  2. GeekDot

    Quadra 950 PSU died... <cry>

    That was my initial thought... then feature-creep struck And who knows when I actually find the time to fully draw that PCB... And we all know: Makeshift solutions last the longest.
  3. Some years later... Just in case you're looking for help with your Quadras PSU... go over there - it has the correct pinouts, the ones from xlr8yourmac are wrong!:
  4. GeekDot

    Quadra 950 PSU died... <cry>

    Because there was no alternative, that's the route I took... and hey, Lady Quadra is alive and kicking again! For those who will ever be in the same situation, here's the how-to with pictures and stuff: Fixing the Quadra power-supply (Ah, and the correct pinout of the power-plug - which is documented wrong elsewhere...)
  5. GeekDot

    Quadra 950 PSU died... <cry>

    Thanks for helping everyone! That somehow is what troubles me. I huffed and puffed and and... got a cut in my finger @Bolle: Is the logic for the soft-power (tickle) on a separate board? That would render the ATX PSU replacement into a real option. So while @Unknown_K's hint "open it up and see" is a good one I'm still stuck at "open it up" - and I don't want to ruin the case (too) or get more cut fingers. Is it possible that I have to somewhat pull out the wire harness going to the mainboard-connector?
  6. Hey gang, I could cry like a baby... Restaurated my Q950, cleaned it, gave it a nice retrobright sunbath, tidied-up the A/UX installation and being annoyed by the loud fan, I went for the final step replacing it with something more silent and while at it, I gave the PSU a good blow of fresh air to undust it. Power-on and..... bzzzzzzt, poof, holy smoke. The PSU went the way of the dodo (Nope, the polarity of the fan was correct) - Only god knows if it was the undusting or just about time to die... So here's my request for help: a) How do I get that damn PSU opened?! All screws removed and it's clear that there are 2 case parts sticked together but they don't move a bit From the outside I can see a bursted varistor near the back-end of the PSU. So that's where the smoke came from... b) Does anybody know where to get a new Q9xx PSU preferably in Europe (given its weight)? Thanks for helping & Cheers, Axel
  7. Not that it'll be of much help, but I have the very same behaviour with my Q950 "Backup-Board" - just did some summer-cleaning and had that 2nd board which I had added a socket to the CPU oscillator some years ago. No chime, no video. It does react to power-on through ADB. All caps look good to me...
  8. GeekDot

    Carrera SE/40

    Pics from/for the Carrera 040 in SE/30 effort
  9. GeekDot

    SCSI2SD + Hard-Reset = No booting

    Nothing fancy, just plain simple 50pin SCSI, molex, no caching.
  10. GeekDot

    SCSI2SD + Hard-Reset = No booting

    Oops, sorry. Yes it's v5... about 3 months old. Works like a charm until the system is not shut down properly. When booting from floppy, there's nothing else need to be done. Just boot from floppy, immediately select "restart" from menu, floppy ejects, SCSI2SD boots just fine. Voodoo...
  11. Hi all! This drives me crazy... I have a SCSI2SD (recent firmware) in my IIci, Sys 7.5.3, all parameters set in "safety mode" (ie. SEAGATE vendor etc.) but formatted and setup with LIDO anyhow and everything's fine and shine... ...until I have to hard-reset the machine - which I have do a lot during current Carrera 040 CP hacking... as soon I've reseted my IIci (using the reset button) it somehow gets confused and cannot boot off the SD anymore, the SCSI2SD LED blinks one, Happy Mac, 2nd blink and then showing the crossed-disk icon. After booting from a Sys 7.5 boot floppy and restarting it using the menu entry everything's ok again. Until the next hard-reset... Any Idea what this can be? It really slows me down in analyzing that damn CP... Cheers, Axel
  12. GeekDot

    Carrera040 Info / Hacking Thread

    Well, yes you do. Bolle an I are „ze Gerrrmans“ in here. The 2 German pages in the AMD doc are just the same as the previous English ones... 1:1 translation. No secrets there... quick update on digging through the CP code: I’m 99% sure to have found the ‚crash area‘, leading to the undocumented,mystery lomem globals. I’m currently comparing that between my IIci and SE/30. Quite a drag constantly swapping the C040 back and forth. Generally, the CP is quite complex, many traps are going to be patched in there, 68882 emulation for the 040 been added, lots of cache handling etc etc...
  13. Hey Gang, While diging, biting and crawling through the Carrera040 disassembly I got to the point where I need to know more about the "Boot Globals" risiding in lowmem's system global variables. BootGlobPtr lives at $DDC, that's for sure, and it points to different locations on different machines - that's what a pointer was meant for. So far so good, but what's the structure of the data living there? Besides some Emulator source, I can't find anything on the web providing more insight... Does anyone in here have a hint or can remember where to look it up? Cheers, Axel
  14. GeekDot

    Carrera040 Info / Hacking Thread

    Very nice! Good to have you in same „setup state“. How many probes does your LA have? Can you check/see 0x53000000 activities (in and out)? I‘m getting closer and closer to the crash point... the tricky thing is, that the CP crashes into the grey boot screen, even from MacsBug. So a simple „go“ and the look at the PC/SP, stack and registers doesn’t work here... Here's an example getting closer to the "point of no return", CP icon loaded, back in enumeration of the init resources... A 2nd screen would help, but my Color Pivot doesn’t have a cable and I prefer spending time with understanding the code than hunting for parts. (Will have just the next week before going on vacation for 16 days...)
  15. GeekDot

    Carrera040 Info / Hacking Thread

    Just for clarification: SwapMMUmode has nothing to do with 030 vs 040. This most often called function switches from 24 (dirty) to 32 (clean) mode... and back. It needs to be called as soon you need to access anything beyond 8MB.