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No Power...

By flight_lieutenant ·
Hey there, I recently built up a new pc for my grandad nothing major just some parts to give him a fairly fast home computer. However after correctly fitting all the parts for him and placing all the wires in the correct places (according to the mobo manual)i came to discover that no power was going through to everything or no LED lights were coming on. I tried using three different psu's all of the same power and three different plugs. This still didnt work. So then i tried using my grandad's new cpu, fan, psu, ram in my pc and they all worked. I then decided that the problem must be in the motherboard, therefore i bought a new one and exactly the same problem arose. Please could anyone help...

There hardware is as follows:

AMD Duron 1600
PC Chips Mobo (Skt A)
Heatsink & Fan (With Grease)
128MB PC2100 RAM
350W PSU

Cheers - Simon

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by Juergen Hartl In reply to No Power...

is the fan in the PSU running?
If yes use a Voltmeter to check the voltages in the lead that goes to the Mobo. If the voltages are ok the Mobo is shot.

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by flight_lieutenant In reply to
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by flight_lieutenant In reply to No Power...

Hey, thanks for the help. The PSU fan isnt spinning but i tried 2 different mobo's so i cant see it being the mobo

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by TheChas In reply to No Power...

Start with the connections for the case lights and switches.

Make sure that you have the power switch leads on the correct terminals.

Make sure that the clear CMOS jumper is not set to the clear position. Many motherboards ship with the jumper set to the clear position, and this will prevent the PC from booting.

Double check the voltage switch on the back of the power supply.

Does the motherboard have an LED on it?
If so, with the power supply plugged in, this LED should glow. That signifies that the 5 volt standby power from the power supply is present.

Next, are you sure that this motherboard supports the 1600MHz Duron?
I have had numerous problems with socket A motherboards not booting because they did not set the CPU speed properly.
If the 1600 MHz Duron is not listed as a supported CPU by PC Chips, you may need to manually set the CPU speed in order for it to work at all.

What I do, is remove both the power cord and CMOS battery for at least 1/2 hour.

Then plug the power cord in and boot up.
Assuming it boots, enter BIOS setup and manually set the CPU Front Side Bus speed and multiplier.
Save settings, and install the CMOS battery.


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by TheChas In reply to

Got your messages.

Since you have a volt-meter, it's time to start checking the power supply lines.

Here is the ATX power connector pins and voltages.

1 3.3V Orange +3.3 VDC
2 3.3V Orange +3.3 VDC
3 COM Black Ground
4 5V Red +5 VDC
5 COM Black Ground
6 5V Red +5 VDC
7 COM Black Ground
8 PWR_OK Gray Power Ok (+5V & +3.3V is ok)
9 5VSB Purple +5 VDC Standby Voltage (max 10mA)
10 12V Yellow +12 VDC
11 3.3V Orange +3.3 VDC
12 -12V Blue -12 VDC
13 COM Black Ground
14 /PS_ON Green Power Supply On (active low)
15 COM Black Ground
16 COM Black Ground
17 COM Black Ground
18 -5V White -5 VDC
19 5V Red +5 VDC
20 5V Red +5 VDC

Pin 9, purple should have 5 volts on it whenever the power supply is plugged in.

Pin 14, green, should be near 5 volts, and switch to near 0 volts when you press the power switch on the case.
For that matter, both power switch pins should be at the same voltage when you press the switch.
(Perhaps the power switch is bad.)

Pin 8, gray, switches from ground to 5 volts when the power comes up and both the power supply and the motherboard agree that everything is okay.

Have you tried a minimum system?
Just CPU, 1 DIMM and the video card plugged in.
It could be a drive or plug-in card issue.

For that matter, do you have a spare CPU around that is on the list of supported CPUs for the motherboard?
It may be as simple as the fact that the motherboard cannot recognize the CPU and will not boot.


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by flight_lieutenant In reply to No Power...

Cheers for your help Chas, all the switches from the front panel are inserted correctly in the right slots... As for an LED on the mobo, there isnt one on it. My AMD Duron 1600 is compatible with the mobo. I am gonna see if your idea about taking the battery out for 30mins works. Also the motherboard didnt have any jumper cables included im a bit unsure about using jumpers...

Anyway, thanks very much for the help it is appreciated...

Simon (flight_lieutenant@hotmail.com)

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by willcomp In reply to No Power...

We'll try to narrow down things. Remove mobo and power supply from case. Install CPU, CPU cooler, and RAM. Place modo on foam or bubble wrap that it came with. Connect power supply to mobo. Try booting with this minimal configuration. To power up, short power switch (soft power) connectors on mobo momentarily with a jumper. Rob one from CD ROM or HDD if need be.

If she boots in minimal configuration, place mobo in case, connect power supply, and try again using jumper in place of power switch. If it boots up, sequence peripherals and connections on starting with power switch. If no boot with mobo installed in case, you may have a grounding or shorting problem with mobo mounts. Ensure there are no extra metal standoffs or other metal objects contacting bottom of mobo.

Post back with results if you need additional info after the above steps.

Good luck,


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by willcomp In reply to

I'm assuming that video is on mobo since it's a PC Chips board. If not, you need to insall video card during bench testing.

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by flight_lieutenant In reply to No Power...

Hey Again everyone that helped me... Ok here goes, i managed to successfully get the computer turned on, i used Charlies idea about the CMOS jumper but i used 2 screwdrivers two connect two pins together and it worked, then i placed the Jumper cover back on and it worked... However there is a problem, even though everything now turns on, the monitor doesnt... Any ideas???

Cheers for everyone that helped me with this, i appreciate it...


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by flight_lieutenant In reply to No Power...

Hey there everyone that helped me... I managed to get evrything to work now, i don't know what happened but i turned the computer back on and it worked!!!

Anywayz, thanks to everyone that helped me with this problem...

Cheers - Simon

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