PowerMac 5400 wont power on?

I recently got a PowerMac 5400 from a yard sale for $5, just because i was bored.

I took it home and plugged it in and flipped the switch on the back and i can hear the monitor click like it was turned on, but nothing else and the screen remains black. I took the cover off (although not the metal heat shield like thing because there is one screw that is on SO tight i cannot get it off for now) and there is one cable with nothing connected to it on the side i can see and its taped down in the back with some yellow tape, i dont know if it is supposed to be like that or not. It has a CD and hard drive. They lady told me it worked (GRRR) and that her husband rebuilt computers, which i believed her because there was a lot of other computers in the back of their garage not for sale.

What could it be?

Could it be because i do not have a mouse or keyboard (I dont have any of the old ADB type anymore)

THanks,

Tanner.

Well, the power switch was on the keyboard for those if I am not mistaken

Finding an ADB keyboard would be a good place to start.

Well there is a switch on the back above the plug and when you flip it the monitor sounds as if it turned on but the screen is black and nothing happens.

Looking on some of the pictures of the keyboards I dont see a power button just by looking at the pictures but maybe there is one, I dont know. I'll keep looking.

The power button on an ADB keyboard is a single key in the upper right corner.
It has a triangle on it that points to the left.

Hope that helps.

I have a 5400. Be right back. Been a while since I booted it up but pretty sure it needs an ADB keyboard.

Mine is a Tower 6400. Got the models confused. The 5400 has a built in monitor. That the one you have?

Ok got out my 5200 which is the basic same thing as your 5400. That Switch in the back is the Power Supply off and on like some PC's have on their power supplies. That turns on the power to the supply but you still need an ADB keyboard to turn on the machine.

Ok great thanks, now ill buy a keyboard i guess (although they are more expensive because of their heavy weight) thanks a lot!

Wait wait wait, here is a thought,
I have so many extra USB keyboards, and i really dont want to buy an ADB keyboard, so can i install a USB card in the PCI slot in the Power Mac and then use an old usb g3 keyboard?

The ADB keyboard had a power-on button all by its lonesome in the upper right corner. But the push switch on the back of the computer will turn the unit on, you do not need a ADB keyboard. If that switch doesn't give you a POST test startup chime then the power supply or the mobo is dead. I wouldn't spend a dime more until you can test the power supply!
Incidentally, if you do put in a USB card your USB keyboard isn't going to have a power-on switch, unless it is one of those MacAlly boards.

ADB keyboard.

Sherman Homan said:

The ADB keyboard had a power-on button all by its lonesome in the upper right corner. But the push switch on the back of the computer will turn the unit on, you do not need a ADB keyboard. If that switch doesn't give you a POST test startup chime then the power supply or the mobo is dead. I wouldn't spend a dime more until you can test the power supply!
Incidentally, if you do put in a USB card your USB keyboard isn't going to have a power-on switch, unless it is one of those MacAlly boards.

Click to expand...

So, i do not have to have the keyboard to turn the computer on, i just use the switch? I thought that just turned the monitor on didnt it?

http://developer.apple.com/document...Notes/Macintosh_CPUs-PPC_Desktop/PPC_5400.pdf

I own the machine. Have turned it off and on for years. Search this official Apple PDF. Search for Power Switch. Soft Power On is the keyboard switch or an apple remote control. Also search for Power Key.

It's true a lot of Power Macs had a Soft power button on the back, but not the 5200-5400. That is a HARD power switch like on PC power supplies. Soft is controlled by the keyboard power or in this case an optional remote control. I dug mine out and fired it up. Only the keyboard power button will power it on.