power consumption Power Mac G4

Question

Level 1

5 points

power consumption Power Mac G4

My power supply blew up though the unit was plugged into a UPS. I would like to know the power consumption of the G4. the MGE UPS Co. lists it at 380 watts but my volt x ampere computation gives 110V x 6.5A = 715 watts. What is it really?

Posted on Sep 19, 2005 1:35 AM

Reply

Answer 1

Alex Lu

Level 3

645 points

Sep 19, 2005 7:57 AM in response to Ana Colayco

Power supplies randomly blow up, this is normal, especially after 3-4 years of use.

The 110V * 6.5A figure is probably a peak load including the monitor. It would surprise me if the G4 consumed more than about 250W with the monitor off, and 450W with the monitor on. The 380W is probably the maximum theoretical load excluding a CRT monitor. (CRT monitors are more power hungry than LCD monitors; LCD monitors are about 20W-40W, and CRT monitors are 100W-250W.)

A G4 at idle with not much RAM and drives off and no USB devices except keyboard and mouse should consume no more than 120W.

So the question is whether your screen is plugged into the UPS, and whether it is an LCD or a CRT screen.

Reply

Answer 2

Ana Colayco Author

Level 1

5 points

Sep 20, 2005 8:03 AM in response to Ana Colayco

Alex, this is meant to be a reply to your message, thanks! That explains it all very clearly. My poor ol Mac is not even two years old, but I live in the back of beyond where electricity problems are aplenty. So that's what the Mac technicians here have told me caused the power supply to blow. they changed the power supply and it still wasn't working so they replaced the logic board and it still didn't work all that well so now they're replacing the power supply yet again... well, when and if it does work fine again, I'll get a 1500VA UPS (good for maximum 1000VA consumption)online double conversion type, that should do it, right? I mean keep the mains power completely away from the Mac! Thanks again, you were a big help! Hard to believe but nobody here could give me a straightforward answer.

Reply

Answer 3

Alex Lu

Level 3

645 points

Sep 20, 2005 9:34 AM in response to Ana Colayco

You are welcome. Back of beyonds have the same probability of lightening strikes as us urban dwellers, it's just that when a lightening does strike in an urban area, it tends to strike something other than the power transmission lines because there are plenty of tall buildings for it to choose from!

Be sure your UPS has a surge protection function.

Also you should be aware no UPS will protect you against a direct lightening strike. It will lessen the likelihood of any given lightening strike in the area damaging your computer, but it is not an absolute guarantee.

Be sure when you retrieve your Mac from the repair shop, to retrieve the DEAD logic board and the DEAD power supply, particularly if they charge you for the replacement parts. The should charge you for the replacement parts that they actually use in your computer, and not anything else they may have used in trying to get your computer to work. Any parts they replace they should give you back the original, DEAD parts (for you to sell on eBay).

Reply