Re: [q] Centris 650 Problems
Date: Tue, 6 Dec 2005 16:56:46 -0800 (PST) From: Nick [EMAIL PROTECTED] Subject: [q] Centris 650 Problems I was hoping someone could give me some suggestions for a sick Centris 650. I had it in storage for a while and before I put it in, it worked great. Once I took it out, however, I couldn't get it to turn on at all. It appears to be dead. I can't get the fan to come on or get a chime or anything. As far as I can tell, everything is fine. I even pulled the SIMMs to see if that would help. I also replaced the PRAM battery and nothing worked. At this point, I am at a loss. At any rate, I would appreciate any suggestions or tips anyone can offer me on getting this Centris 650 back from the grave. I'd hate to scrap it as it's a fine machine. Most likely the some capacitors in the power supply or on the motherboard have given up the ghost. Examine the motherboard carefully for a slightly dark discoloration around the area where the power supply plugs into the MB. If it looks like there's a cola stain on there, then your surface mount electrolytic capacitors (look like tiny silver storage tanks) have leaked their electrolyte onto the board. If the MB caps have leaked you could have three problems. The electrolyte is somewhat conductive and can cause shorts. This is corrected by cleaning the MB. Some folks run them through the dishwasher, but I recommend a careful scrubbing with 91% isopropyl alcohol (or spray with Flux remover and scrub). A soft bristle or worn out toothbrush is good for scrubbing. The electrolyte is corrosive and may have eaten through traces, solder joints or vias (conductive holes through the motherboard) on the motherboard. If this is the case, you would need to identify the damaged area and either resolder damaged solder joints or bypass with wire wrap (for damaged traces or vias). There are about four of these caps that are important to the power-on circuitry. If those caps stop working, then the machine won't stay on. However, this problem more commonly has the symptom that the machine powers on for a moment and then turns off. If these caps are dead then you need to replace them. If you have leaky caps, you really ought to replace them all anyway, because they could continue to leak. If you use two 15W soldering pencils (Radio Shack $10 each) it is easy to remove the surface mount caps. Just apply one pencil to each side and gently lift the cap when it comes loose. Alternatively, your power supply may be history. Again, the electrolytic capacitors in the supply are the most likely culprit, but this time you'd be dealing with through-hole caps rather than tiny surface mount caps. Replacing the caps in the power supply might fix it. You can use the power supply from the following Macs in the Centris 650: Mac IICX, IICI, IIvi, IIvx, Q700, C650, Q650, PM7100. Motherboards for the Centris 650 are not uncommon on Ebay and generally under $15. You can also use the motherboard from a Quadra 650 or a Q800. Your CPU chip is almost certainly still fine, so you could even get a MB with no CPU and just move it over, which might save you a bit. I like the seller, Olde Mac Milt (olde-mac-milt), so you might contact him and see if he has a C or Q650 motherboard available. Oops, just checked and it looks like he's in the process of moving. Jeff Walther -- Quadlist is sponsored by http://lowendmac.com/ and... Small Dog Electronicshttp://www.smalldog.com | Enter To Win A | -- Canon PowerShot Digital Cameras start at $299 | Free iBook! | Support Low End Mac http://lowendmac.com/lists/support.html Quadlist info: http://lowendmac.com/lists/quadlist.shtml -- AOL users, remove mailto:; Send list messages to: mailto:quadlist@mail.maclaunch.com To unsubscribe, email: mailto:[EMAIL PROTECTED] For digest mode, email: mailto:[EMAIL PROTECTED] Subscription questions: mailto:[EMAIL PROTECTED] Archive: http://www.mail-archive.com/quadlist%40mail.maclaunch.com/ iPod Accessories for Less at 1-800-iPOD.COM Fast Delivery, Low Price, Good Deal www.1800ipod.com
Re: [q] Centris 650 Problems
--- Jeff Walther [EMAIL PROTECTED] wrote: Date: Tue, 6 Dec 2005 16:56:46 -0800 (PST) From: Nick [EMAIL PROTECTED] Subject: [q] Centris 650 Problems I was hoping someone could give me some suggestions for a sick Centris 650. I had it in storage for a while and before I put it in, it worked great. Once I took it out, however, I couldn't get it to turn on at all. It appears to be dead. I can't get the fan to come on or get a chime or anything. As far as I can tell, everything is fine. I even pulled the SIMMs to see if that would help. I also replaced the PRAM battery and nothing worked. At this point, I am at a loss. At any rate, I would appreciate any suggestions or tips anyone can offer me on getting this Centris 650 back from the grave. I'd hate to scrap it as it's a fine machine. There motherboard and power supply are perfectly clean. No dark stains. Most likely the some capacitors in the power supply or on the motherboard have given up the ghost. Examine the motherboard carefully for a slightly dark discoloration around the area where the power supply plugs into the MB. If it looks like there's a cola stain on there, then your surface mount electrolytic capacitors (look like tiny silver storage tanks) have leaked their electrolyte onto the board. If the MB caps have leaked you could have three problems. The electrolyte is somewhat conductive and can cause shorts. This is corrected by cleaning the MB. Some folks run them through the dishwasher, but I recommend a careful scrubbing with 91% isopropyl alcohol (or spray with Flux remover and scrub). A soft bristle or worn out toothbrush is good for scrubbing. The electrolyte is corrosive and may have eaten through traces, solder joints or vias (conductive holes through the motherboard) on the motherboard. If this is the case, you would need to identify the damaged area and either resolder damaged solder joints or bypass with wire wrap (for damaged traces or vias). As far as I can tell, all the capacitors are fine. I have read about the capacitor plague but I think that's been more recent and has mostly effected PC hardware. The power supply circuit boards looke clean too. And even if I could just replace the caps, I have zero skill with a soldering iron. There are about four of these caps that are important to the power-on circuitry. If those caps stop working, then the machine won't stay on. However, this problem more commonly has the symptom that the machine powers on for a moment and then turns off. If these caps are dead then you need to replace them. If you have leaky caps, you really ought to replace them all anyway, because they could continue to leak. If you use two 15W soldering pencils (Radio Shack $10 each) it is easy to remove the surface mount caps. Just apply one pencil to each side and gently lift the cap when it comes loose. I'm kind of looking for a no cost/super low cost solution as I'm a college student. Much of the Mac stuff I have is from Goodwill or sometimes people just giving their old stuff away. If I ever pick up a compatible power supply or motherboard I could plop those in. But I wouldn't want to gut a working Quadra just to revive a Centris. Alternatively, your power supply may be history. Again, the electrolytic capacitors in the supply are the most likely culprit, but this time you'd be dealing with through-hole caps rather than tiny surface mount caps. Replacing the caps in the power supply might fix it. Do you know anything about the fuse? You can use the power supply from the following Macs in the Centris 650: Mac IICX, IICI, IIvi, IIvx, Q700, C650, Q650, PM7100. Motherboards for the Centris 650 are not uncommon on Ebay and generally under $15. You can also use the motherboard from a Quadra 650 or a Q800. Your CPU chip is almost certainly still fine, so you could even get a MB with no CPU and just move it over, which might save you a bit. I like the seller, Olde Mac Milt (olde-mac-milt), so you might contact him and see if he has a C or Q650 motherboard available. Thanks very much for your help. Oops, just checked and it looks like he's in the process of moving. Jeff Walther -- Quadlist is sponsored by http://lowendmac.com/ and... Small Dog Electronicshttp://www.smalldog.com | Enter To Win A | -- Canon PowerShot Digital Cameras start at $299 | Free iBook! | Support Low End Mac http://lowendmac.com/lists/support.html Quadlist info: http://lowendmac.com/lists/quadlist.shtml -- AOL users, remove mailto:; Send list messages to: mailto:quadlist@mail.maclaunch.com To unsubscribe, email: mailto:[EMAIL PROTECTED] For digest mode, email: mailto:[EMAIL PROTECTED] Subscription questions: mailto:[EMAIL PROTECTED] Archive: http://www.mail-archive.com/quadlist
[q] Centris 650 Problems
Greetings, I was hoping someone could give me some suggestions for a sick Centris 650. I had it in storage for a while and before I put it in, it worked great. Once I took it out, however, I couldn't get it to turn on at all. It appears to be dead. I can't get the fan to come on or get a chime or anything. As far as I can tell, everything is fine. I even pulled the SIMMs to see if that would help. I also replaced the PRAM battery and nothing worked. At this point, I am at a loss. The only thing I can think of trying is to replace the fuse in the power supply. I have no idea if the fuse is blown or not (it's opaque so I can't see the filament) but I figure it's worth a try. Unfortunately, I can't find a replacement fuse around here. At any rate, I would appreciate any suggestions or tips anyone can offer me on getting this Centris 650 back from the grave. I'd hate to scrap it as it's a fine machine. Thank you. -Nick __ Yahoo! DSL Something to write home about. Just $16.99/mo. or less. dsl.yahoo.com -- Quadlist is sponsored by http://lowendmac.com/ and... Small Dog Electronicshttp://www.smalldog.com | Enter To Win A | -- Canon PowerShot Digital Cameras start at $299 | Free iBook! | Support Low End Mac http://lowendmac.com/lists/support.html Quadlist info: http://lowendmac.com/lists/quadlist.shtml -- AOL users, remove mailto:; Send list messages to: mailto:quadlist@mail.maclaunch.com To unsubscribe, email: mailto:[EMAIL PROTECTED] For digest mode, email: mailto:[EMAIL PROTECTED] Subscription questions: mailto:[EMAIL PROTECTED] Archive: http://www.mail-archive.com/quadlist%40mail.maclaunch.com/ iPod Accessories for Less at 1-800-iPOD.COM Fast Delivery, Low Price, Good Deal www.1800ipod.com
