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sdebnath
Mar 8, 2005, 02:12 PM
Hello,

So I recently bought a Dell 2001FP off my friend, and ran in to the problem where my LCD (connected via DVI) started blanking/flashing at 1600x1200 resolution. I did a bit of research and found several sites saying that this particular LCD has problems with doing 1600x1200 via DVI.

http://forums.us.dell.com/supportforums/board/message?board.id=dim_monitor&message.id=33721
http://www.pricegrabber.com/rating_getprodrev.php/product_id=2313337/id_type=M/

However, here's the twist. This only happens when my powerbook is plugged in to the AC adapter while the LCD is connected. If I disconnect the power source to the powerbook (running off battery while LCD is plugged to the wall), the LCD stops flashing. At first I thought that it might be a problem with the particular socket, but nope, tried all the sockets, and still the same problem.

Bought the powerbook January '04, and it is running Mac OS X 10.3.8. 1.25GHz proc, w/ 512 MB ram, ATI Radeon (for sure) 9200 (?) w/ 64MB video ram. Updating drivers from ATI's support site didn't help either.

Stuff from system profile:
ATY,RV350M10:

Type: display
Bus: AGP
VRAM (Total): 64 MB
Vendor: ATI (0x1002)
Device ID: 0x4e50
Revision ID: 0x0000
ROM Revision: 113-xxxxx-117

Anyone else ran into this problem? If someone has anything that I could try I am up for it. Not sure but if I connect it with a VGA cable instead and then use the Apple's DVI adapter, would that help any? possibly settle timing issues between the card and lcd. But then again why is it only when my powerbook is plugged in?

Thanks!
Shawn :confused:

Monk Edsel
Mar 9, 2005, 04:26 AM
I don't see how it is possible for you to correct the problem by unplugging the PowerBook from the AC, because if you unplug a PowerBook with an external display attached, the PowerBook automatically goes to sleep and will not reawaken until the AC is plugged back in, or you disconnect the display.

blodwyn
Mar 9, 2005, 11:34 AM
I don't see how it is possible for you to correct the problem by unplugging the PowerBook from the AC, because if you unplug a PowerBook with an external display attached, the PowerBook automatically goes to sleep and will not reawaken until the AC is plugged back in, or you disconnect the display.

This is incorrect, I just pulled the power plug on my PB which is connected to an external display, and it carried on working as normal.

Monk Edsel
Mar 9, 2005, 02:06 PM
Curious:

"Connecting an external monitor increases the power requirements of the PowerBook. Therefore, you must use the AC adapter whenever the PowerBook is connected to an external monitor. The PowerBook will not wake up if the power adapter is not connected, and if you disconnect the power adapter the computer will go to sleep."

http://docs.info.apple.com/article.html?artnum=88064

My PowerBook does indeed exhibit this behavior. Thoughts?

blodwyn
Mar 9, 2005, 04:54 PM
Curious:

"Connecting an external monitor increases the power requirements of the PowerBook. Therefore, you must use the AC adapter whenever the PowerBook is connected to an external monitor. The PowerBook will not wake up if the power adapter is not connected, and if you disconnect the power adapter the computer will go to sleep."

http://docs.info.apple.com/article.html?artnum=88064

My PowerBook does indeed exhibit this behavior. Thoughts?

Don't know why there's a discrepancy, I'm currently typing this entry with an external monitor connected and my power unplugged - 12" G4 1.33GHz running 10.3.8.

Mechcozmo
Mar 9, 2005, 05:52 PM
Curious:

"Connecting an external monitor increases the power requirements of the PowerBook. Therefore, you must use the AC adapter whenever the PowerBook is connected to an external monitor. The PowerBook will not wake up if the power adapter is not connected, and if you disconnect the power adapter the computer will go to sleep."

http://docs.info.apple.com/article.html?artnum=88064

My PowerBook does indeed exhibit this behavior. Thoughts?

I connect all the time to an external monitor while on battery power. No issues. mini-DVI to VGA then VGA extension cable to projector. Oh, yeah! :D