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| Click here to select a new forum. | | Q950 Won't Boot | Posted by: retrotech42 on 2017-09-04 18:45:23
I have a Q950 that won't boot up properly. When I power it up, there is a startup chime, but it is very distorted and hardly recognizable. The only video output is a distorted blue screen. I've tried two monitors, a Color Display and a generic Dell VGA with a DB-15 adapter. I've tried reseating the RAM and unplugging/plugging back in the hard drive/CD drive. Is this a sign of capacitor failure? Or has something else gone wrong with the logic board? Thank you for help in advance.
| Posted by: Unknown_K on 2017-09-04 20:50:17
Quadra 950's use tantalum capacitors so no leaks. There is built in VRAM and 4 VRAM sockets, make sure if there are VRAM SIMMs installed they are the correct type and speed. Use a known good video adapter. I keep old generic 640x480 (no settings) ones around just to check machines when I get them (works on all machines and all monitors). Are you using a Nubus video card or built in video?
Make sure the RAM is installed correctly (you need matched sets of 4 and they are split 2 in the top bank and 2 in the bottom).
http://computers.popcorn.cx/apple/macintosh/quadra950/quadra950-04.jpg<=== picture of the motherboard for reference.
| Posted by: Aoresteen on 2017-09-08 02:10:54
Check the CMOS/PRAM battery. weak/bad batteries can cause boot issues.
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