Welcome to Comcast Help & Support Forums
Find solutions, share knowledge, and get answers from customers and experts

New to the Community? Start here.

5,709,660

members

52

online now

1,872,970

discussions

Back to Top

iMac goes to sleep HELP!

Posted by
New Poster
  • Thank you contributor for your first reply to the community!
 Posting replies is the best way to get involved.
  • Congrats on Posting your first topic!

Message 1 of 22
5,119 Views

Just 1 week ago, my imac g5 started acting strange.  It shuts down without warning.

 

I did some troubleshooting, and believe it is shutting down if the network cable is plugged into the computer.  If I take it out, the computer runs smoothly.  If I plug in the network cable, in less than 30 seconds the computer shuts down.

 

I took it to Best Buy and the apple store with my network cable, and both places came back and said there didn't seem to be anything wrong with it, even testing my cable. Diagnostics showed NIC is fine, and power settings.

 

Could there have been a firmware or software update to my cable modem that is causing these problems with my computer?

 

Can I get my modem reset or flashed? Or maybe it needs to be replaced...

 

FYI:  I am connected to the modem directly, I do not have a router

 

Thank you.

21 REPLIES
Posted by
Networking Expert

Message 2 of 22
5,104 Views

 


junsct wrote:

Just 1 week ago, my imac g5 started acting strange.  It shuts down without warning.

 

I did some troubleshooting, and believe it is shutting down if the network cable is plugged into the computer.  If I take it out, the computer runs smoothly.  If I plug in the network cable, in less than 30 seconds the computer shuts down.

...

 

FYI:  I am connected to the modem directly, I do not have a router


 

I suggest that if it works wirelessly, then buy a wireless router and use it.  This solves your problem directly and provides insurance against a lightning strike/power surge via the modem which has been known to happen.  (I also highly recommend a surge protector for your own equipment from the AC power.)

sam




Community Icon
I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee.

Was your question answered?
Mark it as a solution!solution Icon

Posted by
Problem Solver

Message 3 of 22
5,098 Views
Posted by
Silver Problem Solver

Message 4 of 22
5,092 Views

 


UHFhd wrote:

HI 

     Is router rented from comcast or owned ? How old is router ? Is it in  list of approved modems? 

   or at end of life                                                                           http://mydeviceinfo.comcast.net/


OP doesn't have a router....I think you meant modem...NM.Smiley Wink

 

Posted by
Problem Solver

Message 5 of 22
5,086 Views
Posted by
Silver Problem Solver

Message 6 of 22
5,081 Views

Try swapping the cable from modem to mac, could be bad. Guess you tried unplugging the modem to reset it?

Posted by
Problem Solver

Message 7 of 22
5,077 Views
Posted by
Silver Problem Solver

Message 8 of 22
5,072 Views

Yeah, I know just saw that...!

Posted by
New Poster
  • Thank you contributor for your first reply to the community!
 Posting replies is the best way to get involved.
  • Congrats on Posting your first topic!

Message 9 of 22
5,057 Views

Kernel Panics.... saw somewhere to reset PRAM.. apparently it will clear KP's.

 

I'm going to try wireless as well.  My neighbor has wireless, i can ask to join for testing. sure they won't mind.

Posted by
New Poster
  • Thank you contributor for your first reply to the community!
 Posting replies is the best way to get involved.
  • Congrats on Posting your first topic!

Message 10 of 22
5,056 Views

Modem is rented, just got service in December.  Will check the modem for EOL

Posted by
Problem Solver

Message 11 of 22
5,041 Views
Posted by
New Poster
  • Thank you contributor for your first reply to the community!
 Posting replies is the best way to get involved.
  • Congrats on Posting your first topic!

Message 12 of 22
5,033 Views

Power settings are already set to never..

 

I did not repair permissions yet...

 

However, did get connected to my neighbors wireless, and system does not shut down.  I think for weirdness sake, I might just get the basic netgear wireless router, and be done with the ethernet connection.

Posted by
Problem Solver

Message 13 of 22
5,024 Views
Posted by
Customer Expert

Message 14 of 22
5,009 Views

I don't like the idea of settling on a wireless router as a "solution". I agree that it avoids the physical connection, but it's often a slower connection. And you need to be sure to lock it down so that your neighbors don't use it without permission.


Crashing is not "going to sleep". Why are you plugging and unplugging your network cable?


Are you running any unusual kernal extensions? Did you install any new software a week ago? 





Community Icon
I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee.

Was your question answered?
Mark it as a solution!solution Icon

Posted by
Contributor

Message 15 of 22
4,996 Views

does this network cable happen to provide power over ethernet? if so then you might be experiencing power troubles.

Posted by
Networking Expert

Message 16 of 22
4,982 Views

 


BethKatz wrote:

I don't like the idea of settling on a wireless router as a "solution". I agree that it avoids the physical connection, but it's often a slower connection. And you need to be sure to lock it down so that your neighbors don't use it without permission.


Crashing is not "going to sleep". Why are you plugging and unplugging your network cable?


Are you running any unusual kernal extensions? Did you install any new software a week ago? 


An iMac g5 has at least an 802.11g wi-fi card.  I doubt that it would run much slower than the Comcast network.  As a $30 router solves a problem and eliminates multiple trips to repair shops which quickly add up to higher costs and waste invaluable time, I suggested a simple solution that resolves the problem.

 

 

A quote to consider:

"Would you tell me please, which way I ought to go from here?
That depends a good deal on where you want to get to, said the cat.
I don't much care where -, said Alice.
Then it doesn't matter which way you go, said the cat"

 

sam

 

 




Community Icon
I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee.

Was your question answered?
Mark it as a solution!solution Icon

Posted by
Customer Expert

Message 17 of 22
4,974 Views

I don't have a problem with wireless. I use a wireless router in my house, but some machines are wired.


But while that works around the immediate symptoms, is there something else going on that caused the problem?




Community Icon
I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.
Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.
Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee.

Was your question answered?
Mark it as a solution!solution Icon

Posted by
Email Expert

Message 18 of 22
4,967 Views

Could you provide more details about what happens? Your subject line says "sleep", but the message said "shuts down". Do you get a kernel panic message when this happens? This is where the screen turns dark and says "You need to restart your computer. Hold down the Power button for several seconds or press the Restart button."

 

If the computer just loses power totally, as if you'd pulled the plug, I suspect some kind of short circuit on the processor board, so that the NIC is somehow connected with the power supply.




Community Icon
I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee.

Was your question answered?
Mark it as a solution!solution Icon

Posted by
Networking Expert

Message 19 of 22
4,961 Views

 


Barmar wrote:

Could you provide more details about what happens? Your subject line says "sleep", but the message said "shuts down". Do you get a kernel panic message when this happens? This is where the screen turns dark and says "You need to restart your computer. Hold down the Power button for several seconds or press the Restart button."

 

If the computer just loses power totally, as if you'd pulled the plug, I suspect some kind of short circuit on the processor board, so that the NIC is somehow connected with the power supply.


The ethernet circuit/chip should be completely separate from the wi-fi card and therefore your conjecture concerning this failure possibility is potentially correct.  A new processor board might cost more than a new computer as I assume that this is an old machine.  As usual, I assume that all of us recommend a complete backup of all user files be maintained.  An external portable usb hard drive of sufficient size costs about the same as a router.  With no huge music or video files, a small usb2 keychain drive would work.

 

sam




Community Icon
I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee.

Was your question answered?
Mark it as a solution!solution Icon

Posted by
Email Expert

Message 20 of 22
4,937 Views

The really confusing thing is that he said they couldn't reproduce it at the Apple store. If there really were a short circuit, it seems like it should fail for them as well.

 

This suggests something specific to his cable modem. If it's old, maybe it's gone bad and is transmitting a bad signal.




Community Icon
I am not a Comcast employee, I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help. For information on the program click here.
We ask that you post publicly so people with similar questions may benefit from the conversation.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee. I am a paying customer just like you!
I am an XFINITY Forum Expert and I am here to help.
We ask that you post publicly so people with similar questions may benefit.

Was your question answered? Mark it as an accepted solution!solution Icon
Community Icon
I am not a Comcast employee.

Was your question answered?
Mark it as a solution!solution Icon

Posted by
Silver Problem Solver

Message 21 of 22
4,930 Views

I'm with Barmar, wouldn't hurt to swap the modem out, just to see.

Posted by
Frequent Visitor
  • You have posted 5 replies to the community. Thank you for keeping the conversations going!
  • Thank you contributor for your first reply to the community!
 Posting replies is the best way to get involved.

Message 22 of 22
4,849 Views

Was the issue with your iMac G5 ever resolved?

I'm a Mac Technician and have long experience with computers like yours so I was curious about your issue.

Shut downs on G5 iMacs are most often related to failing power supplies, however your description leads me to think that there is a short circuit in your modem.

Connecting to ethernet does not usually bring a weak power supply down; processor-intensive tasks are usually the cause.