At 20:27 -0500 04/26/2002, Gary Gorbet wrote: >Now I am assuming that something is wrong in the motherboard. My >question to you all is: can you suggest anything else to try before >I go out and try to score a motherboard or whole other S900? This >machine has been good to me and, now, to my daughter. I would sure >like to get it back on its feet. I had just installed a new G3/500, >more RAM and OS 9.1. Thanks in advance for any suggestions.
These machine should power up even with the CPU removed, as the power-on signal is interpreted by the microcontroller contained in teh CUDA chip. Of course, it won't chime without a CPU installed, but that's not the problem at this point. Why don't you try it with no CPU and no RAM (and no drives connected to PS) and disconnect the front power button cable from the MB, and see if you can get the power to come on using the keyboard button. If not, disconnect the keyboard cable, and see if just the front button will work. Of course, make sure the front button is properly connected for the second test. :-) If neither of those works, then you've either got two bad power supplies, or a bad motherboard. If it's the motherboard, it's possibly the CUDA chip gone bad which is fairly easy to fix if you're a skilled solderer and have almost any older PowerMac board available from which to salvage one (e.g. 6100, 7100, 7200). It is also possible that one or more of the pins in the power supply connectors has a bad solder joint to the motherboard. You may wish to touch up the solder to those. Pay particular attention to the three pin connector pins, as that one supplies the 5V trickle and the Power-On signal line that are essential to turning the machine on. Jeff Walther -- SuperMacs is sponsored by <http://lowendmac.com/> and... Small Dog Electronics http://www.smalldog.com | Refurbished Drives | Service & Replacement Parts [EMAIL PROTECTED] | & CDRWs on Sale! | SPECIAL SM LIST PRICES - 24x Bootable SCSI CDROM $39.99, Umax Processors $19.99 PowerSupplies from C500/C600 $49.99 J700/S900 $79.99 <mailto:[EMAIL PROTECTED]> Support Low End Mac <http://lowendmac.com/lists/support.html> SuperMacs list info: <http://lowendmac.com/supermacs/list.shtml> Send list messages to: <mailto:[EMAIL PROTECTED]> To unsubscribe, email: <mailto:[EMAIL PROTECTED]> For digest mode, email: <mailto:[EMAIL PROTECTED]> Subscription questions: <mailto:[EMAIL PROTECTED]> Archive: <http://www.mail-archive.com/supermacs%40mail.maclaunch.com/> Using a Mac? Free email & more at Applelinks! http://www.applelinks.com
