Re: iMac G5/2ghz 20" random sleep
On Jun 14, 2014, at 7:51 PM, les wrote: > > > On Friday, June 13, 2014 2:51:33 PM UTC-7, les wrote: > Hi All, > My iMac G5 OS X 10.4.11 has been running flawlessly for 11/2 yrs. Suddenly it > randomly completely shuts down. I can start with power switch, but it soon > shuts down again. I opened the case, cleaned thoroughly and inspected caps. > All pristine. Power supply appears clean from outside.I am hesitant to open > it. Does this indicate a PSU problem? Can it be replaced safely? > Thanks, Les > > Thanks Cameron Kaiser, Jim Scott, and Clark Martin for your valuable insight. > Heat does not seem to be an issue as determined by Temp. Monitor. Yes, it > shuts off as if power plug was disconnected. No warning, no logout screen > etc. Jim thanks for the detailed reply. I am encouraged to swap out the PSU. Before you go through all that trouble, spray the switch assembly with WD-40. You might be glad that you did.. -- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list --- You received this message because you are subscribed to the Google Groups "G-Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to g3-5-list+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: iMac G5/2ghz 20" random sleep
On Friday, June 13, 2014 2:51:33 PM UTC-7, les wrote: > > Hi All, > My iMac G5 OS X 10.4.11 has been running flawlessly for 11/2 yrs. Suddenly > it randomly completely shuts down. I can start with power switch, but it > soon shuts down again. I opened the case, cleaned thoroughly and inspected > caps. All pristine. Power supply appears clean from outside.I am hesitant > to open it. Does this indicate a PSU problem? Can it be replaced safely? > Thanks, Les > Thanks Cameron Kaiser, Jim Scott, and Clark Martin for your valuable insight. Heat does not seem to be an issue as determined by Temp. Monitor. Yes, it shuts off as if power plug was disconnected. No warning, no logout screen etc. Jim thanks for the detailed reply. I am encouraged to swap out the PSU. -- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list --- You received this message because you are subscribed to the Google Groups "G-Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to g3-5-list+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: iMac G5/2ghz 20" random sleep
On 6/13/14, 4:51 PM, les simo wrote: Hi All, My iMac G5 OS X 10.4.11 has been running flawlessly for 11/2 yrs. Suddenly it randomly completely shuts down. I can start with power switch, but it soon shuts down again. I opened the case, cleaned thoroughly and inspected caps. All pristine. Power supply appears clean from outside.I am hesitant to open it. Does this indicate a PSU problem? Can it be replaced safely? Thanks, Les -- a quick search for "G5 recapping" produced several links. -- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list --- You received this message because you are subscribed to the Google Groups "G-Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to g3-5-list+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: iMac G5/2ghz 20" random sleep
KK6ISP Yet another designated driver on the information super highway. > On Jun 13, 2014, at 2:51 PM, les simo wrote: > > My iMac G5 OS X 10.4.11 has been running flawlessly for 11/2 yrs. Suddenly it > randomly completely shuts down. I can start with power switch, but it soon > shuts down again. I opened the case, cleaned thoroughly and inspected caps. > All pristine. Power supply appears clean from outside.I am hesitant to open > it. Does this indicate a PSU problem? Can it be replaced safely? First question is, does it shutdown or shut off? By shutdown I mean does it quit applications and log out he user. Or does it suddenly shut off as if you unplugged the power cord? -- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list --- You received this message because you are subscribed to the Google Groups "G-Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to g3-5-list+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: iMac G5/2ghz 20" random sleep
On Jun 13, 2014, at 2:51 PM, les simo wrote: > Hi All, > My iMac G5 OS X 10.4.11 has been running flawlessly for 11/2 yrs. Suddenly it > randomly completely shuts down. I can start with power switch, but it soon > shuts down again. I opened the case, cleaned thoroughly and inspected caps. > All pristine. Power supply appears clean from outside.I am hesitant to open > it. Does this indicate a PSU problem? Can it be replaced safely? > Thanks, Les The power supplies in pre-iSight G5 iMacs are relatively easy to remove and replace safely. Apple originally intended for users to replace most of the components inside G5 iMacs. So, remove and/or loosen any brass-colored screws attaching the power supply to the case. (Silver-colored screws are meant to be removed only by qualified Apple techs.) Then disconnect the power supply cable to the logic board (and detach the ambient light sensor cable if your iMac has one). It usually helps to turn the center latching screw about halfway back in. Then judiciously lift the top or fastening screw side and wiggle the power supply out of its snug compartment. Inside the power supply are about a dozen capacitors. I've seen as many as 9 of them bulging/leaking/blown. There are kits to replace the caps, but my experience is that about half of the repaired power supplies go bad again, and very quickly at that. Those power supplies have silver Torx security screws (hence the little nub in the center of the screw slot), so you'll need a cheap set of Torx security bits with hollow centers to fit over the nubs. Harbor Freight has 'em. Or borrow a T10 Torx security bit from a trusting friend. Pay close attention to how the power supply comes apart as getting the spring-loaded triangular piece back in, as well as the end screws properly located, can be tricky. All said and done, if you see even one suspicious-looking capacitor, your best bet is to find another power supply that's known to be good. Even then, take it apart and clean out all the dust. Of course, turn off the iMac and let it sit for a while plugged in to discharge the caps in the power supply before you take the back cover off. Even then, be careful. I've never been zapped while working on an iMac power supply that I've let discharge that way, but there's always the first time. Apple went to a different power supply design with the iSight G5 and newer iMacs. Why? My guess is that the original philosophy of having incoming ambient air cool the power supplies in G5 iMacs blew up in the designers' faces, in part because that caused heated air to wash over the heat-sensitive faulty capacitors (the stolen electrolyte recipe lacked a key ingredient that stabilized the electrolyte and prevented it from boiling), thus accelerating failures. So realizing the error of its ways as well as those of its supplier, Apple moved subsequent iMac power supplies to the end of the cooling air path instead of at the beginning ... and got rid of that dadblamed case. Also, be aware that a capacitor can look OK and still be faulty and unable to hold correct electrical values, thus causing weird symptoms. And ... it's possible the thermal paste under the heat sink on three chips and between the logic board and the heat sink underneath it has dried out. It's a lot more work but worth the effort if it saves the iMac. Jim Scott Eureka, CA -- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list --- You received this message because you are subscribed to the Google Groups "G-Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to g3-5-list+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
Re: iMac G5/2ghz 20" random sleep
> My iMac G5 OS X 10.4.11 has been running flawlessly for 11/2 yrs. Suddenly > it randomly completely shuts down. I can start with power switch, but it > soon shuts down again. I opened the case, cleaned thoroughly and inspected > caps. All pristine. Power supply appears clean from outside.I am hesitant > to open it. Does this indicate a PSU problem? Can it be replaced safely? First thing I'd think about is heat. Anything interesting in the system log? Usually if it's a heat-related shutdown, there will be a warning about over temperature status. Second thing would be, unfortunately, the PSU. -- personal: http://www.cameronkaiser.com/ -- Cameron Kaiser * Floodgap Systems * www.floodgap.com * ckai...@floodgap.com -- Do not use for personal hygiene. -- Actual label, toilet brush - -- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list --- You received this message because you are subscribed to the Google Groups "G-Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to g3-5-list+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
iMac G5/2ghz 20" random sleep
Hi All, My iMac G5 OS X 10.4.11 has been running flawlessly for 11/2 yrs. Suddenly it randomly completely shuts down. I can start with power switch, but it soon shuts down again. I opened the case, cleaned thoroughly and inspected caps. All pristine. Power supply appears clean from outside.I am hesitant to open it. Does this indicate a PSU problem? Can it be replaced safely? Thanks, Les -- -- You received this message because you are a member of G-Group, a group for those using G3, G4, and G5 desktop Macs - with a particular focus on Power Macs. The list FAQ is at http://lowendmac.com/lists/g-list.shtml and our netiquette guide is at http://www.lowendmac.com/lists/netiquette.shtml To post to this group, send email to g3-5-list@googlegroups.com For more options, visit this group at http://groups.google.com/group/g3-5-list --- You received this message because you are subscribed to the Google Groups "G-Group" group. To unsubscribe from this group and stop receiving emails from it, send an email to g3-5-list+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
