New case and power supply: Won't turn on!

O

oregon

Active Member
I just got a Antec 900 and 650W neopower power supply today. I transferred my motherboard and all my stuff, but when I hit the power button, nothing happens.

I plugged it into the wall, have the switch on 1, attached it to the motherboard, then attached the it to all the fans and drives.

I don't know what I did wrong, but I have two suspicions:

1. The power supply is modular, so I attached a four pipower cable, then wired it to two fans, and the optical drive. With the other cable, I wired it to two more fans and the hard drive. Is this allowed, or is there some sort wiring pattern your supposed to follow?

2. The wirings from the case power buttons... in the manual it mentioned four wirings to attach: reset sw, power sw, power led, and hd led. In my case though, I could only find three: reset sw, the power sw, and the hdled. On my motherboard there's a little diagram that shows how to wire it. It mentions: PWBT, RST, HDLED, and ACPILED. I attached the Power SW to PWBT, RST to reset sw, and hdled to hdled. I don't know what ACPILEP is, and I can't find anything to plug in there. Is my wiring correct?

3. With these connectors I know there's supposed to be + and -. White is on every one of them along with a colored wire. Is white plus or minus?

Those are the only problems I can think of apart from failing parts. I suppose I should say that I bought the new PS and case because I thought my previous power supply had died when my computer suddenly turned off, and the power supply was very hot. Later the PS only (sometimes) made a clicking noise when I tried to turn the computer back on. This is what a dead power supply does, isn't it?
 
First of all the Antec 900 only has the three leads for the power button, reset, and hard drive led which also serves as the power led rolled into one there since that is always somewhat busy or seeing a repeating flash. The typical 12v molex connectors used for ide type drives serve well for the 12v powered case fans. Only the cpu fan(Zalman 9700)) and the 120 put on the side cover here actually plug into the board.

Review the four wire cpu feed to see if that is plugged in near the cpu otherwise nothing will start up on most boards before assuming a doa supply. Also review the old thread seen at http://www.computerforum.com/80790-bad-board-simply-need-replug.html explaining what happened when simply swapping a supply out on the last build to see nothing happen.

Bad supply? Bad board? or maybe a what? Maybe just the simple need to unplug and then lightly "replug back in" the 12v cpu feed due to a loose contact inside the four wire power connector there. Another way would be to simply jump the pins on the board to see if the board is any good and the wires were simply reversed or you got a bac board.
 
I'm not sure what a CPU feed is. The only thing I plugged in from the PS to the motherboard wast the 20 pin connector. The CPU heatsink also plugs into the motherboard, and doesn't go through the power supply.
 
There are 2 connections you need to make to the motherboard from the PSU. 1 is that 20+4 connector, and the other is either a 4 pin or an 8 pin connector that usually connects near the CPU. The 4/8 pin is what actually gives the cpu it's power. The 20+4 connector supplys power to everything else on the motherboard.



4 pin and 8 pin connector. Only 1 of the 2 cpu connectors gets used. It depends on which motherboard you have on which one you will use.

4pin8pin.jpg



And the 20+4 pin connector.

24pin.jpg
 
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sounds like pc eye nailed it head on...there is a small square 4 holed plug you will also need to plug into your mobo along with the main power connection or it will not boot. Its normally located to the left of your cpu on the board :) If thats not it you prolly don't have your power switch connected to the mobo right.
 
Well... I think that may be the problem. The new powersupply has both a four and eight pin connector like the ones above. However, my motherboard doesn't have a port to plug it into. My motherboard is an old ECS K7S5A. However, my computer ran on my old powersupply that only had a 20 pin plug. So wouldn't the CPU feed not be necessary on this motherboard?
 
Pentium 4 model boards were the first ones to need the additional 12v feed for the cpu while still seeing the 20pin main power connection even like an old AMD board would. Being that is an older Socket A board it wouldn't use either the four wire cpu feed or the small 4pin break away plug seen on supplies since.

If you look at the left side of the main power connector in the picture posted by paratwa you will note the small section leaning away there. That slides up and off for using 20 of the 24pins on older boards. Check to see if the 20pin section is all the way in as well as verifying the way the power, reset, and HD led wires are plugged in. That's why unplugging the reset and power to jump the correct pins with something like a paper clip or tip of a screwdriver would determine if the board or supply was bad.
 
PC eye said:
That's why unplugging the reset and power to jump the correct pins with something like a paper clip or tip of a screwdriver would determine if the board or supply was bad.
Click to expand...

Wait... how exactly do you do this? BTW, I'm assuming the supply is working, it's a brand new Antec. I'm buying new stuff anyway, so I'll just not worry about trying to get my current motherboard working. :)
 
With the specified pins exposed you simply toudh across the plus and minus pair for the power. You have to go easy since those can still be bent but a light tap with something made of a conductive metal material would be used. For the split second or so that you hold something across the two pins you are closing an open circuit which is called a momentary switch in order to tell the board to turn itself on.

You can use the breaker switch on the supply afterwards to turn it off. But you would then know if both the supply and board are working. You should already see a green led on the board if equipped on indicating there is enough power available if the main is in and the suppoly itself is supplying the power needed. If that is dark? oops!
 
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