I have a Samsung SyncMaster 730b and a 15” Apple Powerbook G4 (1.67 GHz), powered by the standard Apple 65 watt power adapter. I typically connect my Samsung 730b monitor to my Powerbook to use it as a second display connected through a DVI cable. For some reason my power adapter plugged into the Powerbook is turning itself off, which fails to charge my battery and eventually drains the computer to nothing. I am able to get the power adapter to start charging again if I unplug it from the wall and then plug it back in.
The problem doesn’t happen at consistent time or time intervals. It happened about five minutes ago, but that was the first time it happened since about 14 hours ago. Sometimes the adapter goes off twice in an hour, sometimes it can be several hours or days before it happens.
I am using the grounded three prong cord that attaches to the white apple power block, although the problem also occurs when using the duck head attachment.
I have been troubleshooting the problem for months and have spent a lot of time researching online, including all of the pertinent Apple and Samsung support forums I can find. Apple says that the power adapter shutoff occurs because the AC adapter's over voltage protection feature senses ground noise and turns off the adapter. The company also says that it may not happen if the power adapter is plugged into an uninterruptible power supply (UPS).
I have not tried a UPS yet because it will require a significant purchase and only some users on the support forums have found the UPS to be successful at stopping the power adapter shutoffs. I have reset the PRAM, NVRAM, and PMU that Apple and individual users have suggested and I continue to have the problem. The problem persists no matter what outlets, surge protector, or combination of the two is used for the Powerbook and/or monitor. I normally have additional peripherals connected to my computer, but the problem has persisted without any devices (other than the Samsung monitor) plugged into my computer.
I have had the problem at my current apartment and my previous apartment. I have never had the problem in any other location I have used my laptop, but I have also never used my Samsung monitor in any location other than my current and past apartments. I have connected the laptop to a Westinghouse LCD television for more than a week and used that as a second monitor (to troubleshoot the problem). I have not had a problem with my power adapter while using the Westinghouse as a second monitor. I have only had the problem when my Samsung is connected to my Powerbook. The problem persists whether or not I use a VGA cable with DVI adapter or a straight DVI cable from the monitor to the laptop. The problem does not occur if the monitor is not plugged in to my laptop, regardless of whether or not it is powered on (e.g. my monitor turned on and searching for a signal that isn’t there does not cause the Powerbook to have a problem). The problem also persists whether I set the external monitor to a 60 hz refresh rate or a 75 hz refresh rate.
[b]To recap, the problem is not solved by:[/b]
-Using a different monitor cable
-Using a different power outlet for the computer
-Using a different power outlet for the monitor
-Using a different power outlet for the surge protector
-Using a different surge protector for the computer
-Using a different surge protector for the monitor
-Bypassing the surge protector and plugging the computer straight into the wall
-Resetting the computer’s PRAM
-Resetting the computer’s NVRAM
-Resetting the computer’s Power Management Unit (PMU)
-Using a different refresh rate on the Samsung monitor
-Unplugging all peripherals from the computer except for the Samsung monitor
-Using the computer and monitor in a completely different apartment (on the other side of town)
-using the duck head attachment on the power adapter.
[b]
The problem is solved by:[/b]
-Using a non-Samsung LCD TV as a second monitor
-Not using an external monitor
My troubleshooting leads me to believe that the Samsung monitor is causing a problem through its connection to the computer. I do not believe it is a problem with the monitor’s connection to the power outlets in the apartment because the problem does not occur when the monitor is powered on and unconnected to the computer. I therefore do not believe plugging the monitor and/or computer into a UPS will solve the problem.
I do not believe it is possible for the monitor to be sending electrical noise out of itself and into the apartment’s power outlets, but if it is, I have one additional troubleshooting configuration I would try.
I understand this is an elaborate description of my situation, but I hope it is helpful in showing the isolation of variables and troubleshooting actions I have followed. Have any other users encountered a similar problem? What do you believe the problem to be and what suggestions do you have for me to continue using my Samsung monitor?
Thanks in advance for your assistance.
Do you have another power adapter to try? Sometimes those go bad, and are pretty cheap to test out (around $35-$50). Otherwise it is the DC-in board on your PowerBook. I replace about 2 of those per month with our clients up here on the PowerBooks (and iBooks). The DC-in board on your 15" is also part of your sound board.
156 views
Usually answered in minutes!
×