wont power up

frankmac · 09-30-2009, 12:19 PM

I am running vista basic. I replaced the hard drive and reinstalled the OS. The computer will run fine. I can shut down the computer, but I cannot start it back up without unplugging the power cord and plugging it back in. I have gone through 2 power supplies and still have the same same problem. I have updated the BIOS and reset Bios back to factory settings same problem. replaced the CMOS battery. The battery light on the face of the computer does go out when I shut down and the CPU and case fans run louder. When I unplug and plug it back in the battery light will come on and the fans will quiet down then I can press the power button and it will power power up fine. Any ideas?

**wrench97** · 09-30-2009, 01:59 PM

What Brand and Model Power Supplies are you using?
What Motherboard, CPU and Video Card do you have?

**Tyree** · 09-30-2009, 02:06 PM

Did you install the Mobo drivers?

frankmac · 09-30-2009, 09:29 PM

The computer is a Compaq Presario sr5110nx. Motherboard is a MCP61PM-H M. CPU is AMD Athlon 64 3800+. Video card is NVIDIA GE force 6150SE. The power supply is a bestec model #ATX-250-12z rev D2

**wrench97** · 10-01-2009, 01:27 AM

Both PSU were the Bestec model?

When you shut down the system does it completely turn off? (the reference to

Quote:

when I shut down and the CPU and case fans run louder

)

frankmac · 10-01-2009, 05:37 AM

Yes, both of the PSU's were bestec. As far as I can tell it is shutting down completly. After it powers down I try to push the power button and I get nothing, also the battery light goes out. If I unplug and plug back in the fans speed up and the battery light comes on and then I can press the power button and it illuminates and the computer starts up normal. I checked the power button settings in vist and it is set to shut down and I set the start menu button to shut down

frankmac · 10-01-2009, 05:38 AM

I went through device manager and tried to update all drivers and I was prompted that I had the dest driver installed already

**wrench97** · 10-01-2009, 12:15 PM

I would try a different Power supply if you can. Or if you have access to a digital voltmeter> Test your power supply with a multi meter

frankmac · 10-04-2009, 01:58 PM

I tested the wiring and the green wire #14 was the only one that did not check out. It measured .796 volts and it supposed to be 3-5v.

**wrench97** · 10-04-2009, 02:11 PM

Disconnect the front panel header(the wires to the power switch) and recheck the the green wire.

frankmac · 10-05-2009, 07:44 AM

that voltage was 4.75v

**wrench97** · 10-05-2009, 12:17 PM

After disconnecting the front panel header the PS_On #14 green wire went up to 4.75?

If you can ID the the 2 wires that go to the switch on the front of the case, hook up all the power cables and momentarily touch the 2 pins on the motherboard with the front panel header disconnected and see if it starts, If you can not ID them post back and I see if I can fine a pin out for the heater.

frankmac · 10-07-2009, 02:20 PM

The voltage was with the wires connected. The wires to the power switch are solid. The do not disconnect from the switch. The voltage of the green wire at the power plug with everything plugged in is .796v. The voltage on the back of the power switch on the front of the tower with everything plugged in is 4.75v.

**wrench97** · 10-07-2009, 02:26 PM

From the switch no from the motherboard is where you would disconnect them, however since you were able to get a reading from the switch wire of 4+ volts. It appears to bea power supply that's failed.

09-30-2009, 12:19 PM	#1 (permalink)
frankmac Registered User Join Date: Sep 2009 Posts: 7 OS: vista basic 32 bit	wont power up I am running vista basic. I replaced the hard drive and reinstalled the OS. The computer will run fine. I can shut down the computer, but I cannot start it back up without unplugging the power cord and plugging it back in. I have gone through 2 power supplies and still have the same same problem. I have updated the BIOS and reset Bios back to factory settings same problem. replaced the CMOS battery. The battery light on the face of the computer does go out when I shut down and the CPU and case fans run louder. When I unplug and plug it back in the battery light will come on and the fans will quiet down then I can press the power button and it will power power up fine. Any ideas?

09-30-2009, 01:59 PM	#2 (permalink)
wrench97 Moderator, Hardware Team Join Date: May 2008 Location: S.E. Pennsylvania Posts: 18,485 OS: Win7	Re: wont power up What Brand and Model Power Supplies are you using? What Motherboard, CPU and Video Card do you have? __________________ Power Supply and Selection

09-30-2009, 02:06 PM	#3 (permalink)
Tyree Mentor Hardware Team Join Date: May 2009 Location: Illinois Posts: 5,540 OS: XP Pro-7RC-Mandriva My System	Re: wont power up Did you install the Mobo drivers? __________________ Posting your PC specs will help us to help you quicker and more efficiently.

09-30-2009, 09:29 PM	#4 (permalink)
frankmac Registered User Join Date: Sep 2009 Posts: 7 OS: vista basic 32 bit	Re: wont power up The computer is a Compaq Presario sr5110nx. Motherboard is a MCP61PM-H M. CPU is AMD Athlon 64 3800+. Video card is NVIDIA GE force 6150SE. The power supply is a bestec model #ATX-250-12z rev D2

10-01-2009, 05:37 AM	#6 (permalink)
frankmac Registered User Join Date: Sep 2009 Posts: 7 OS: vista basic 32 bit	Re: wont power up Yes, both of the PSU's were bestec. As far as I can tell it is shutting down completly. After it powers down I try to push the power button and I get nothing, also the battery light goes out. If I unplug and plug back in the fans speed up and the battery light comes on and then I can press the power button and it illuminates and the computer starts up normal. I checked the power button settings in vist and it is set to shut down and I set the start menu button to shut down

10-01-2009, 05:38 AM	#7 (permalink)
frankmac Registered User Join Date: Sep 2009 Posts: 7 OS: vista basic 32 bit	Re: wont power up I went through device manager and tried to update all drivers and I was prompted that I had the dest driver installed already

10-01-2009, 12:15 PM	#8 (permalink)
wrench97 Moderator, Hardware Team Join Date: May 2008 Location: S.E. Pennsylvania Posts: 18,485 OS: Win7	Re: wont power up I would try a different Power supply if you can. Or if you have access to a digital voltmeter> Test your power supply with a multi meter __________________ Power Supply and Selection

10-04-2009, 01:58 PM	#9 (permalink)
frankmac Registered User Join Date: Sep 2009 Posts: 7 OS: vista basic 32 bit	Re: wont power up I tested the wiring and the green wire #14 was the only one that did not check out. It measured .796 volts and it supposed to be 3-5v.

10-04-2009, 02:11 PM	#10 (permalink)
wrench97 Moderator, Hardware Team Join Date: May 2008 Location: S.E. Pennsylvania Posts: 18,485 OS: Win7	Re: wont power up Disconnect the front panel header(the wires to the power switch) and recheck the the green wire. __________________ Power Supply and Selection

10-05-2009, 07:44 AM	#11 (permalink)
frankmac Registered User Join Date: Sep 2009 Posts: 7 OS: vista basic 32 bit	Re: wont power up that voltage was 4.75v

10-05-2009, 12:17 PM	#12 (permalink)
wrench97 Moderator, Hardware Team Join Date: May 2008 Location: S.E. Pennsylvania Posts: 18,485 OS: Win7	Re: wont power up After disconnecting the front panel header the PS_On #14 green wire went up to 4.75? If you can ID the the 2 wires that go to the switch on the front of the case, hook up all the power cables and momentarily touch the 2 pins on the motherboard with the front panel header disconnected and see if it starts, If you can not ID them post back and I see if I can fine a pin out for the heater. __________________ Power Supply and Selection

10-07-2009, 02:20 PM	#13 (permalink)
frankmac Registered User Join Date: Sep 2009 Posts: 7 OS: vista basic 32 bit	Re: wont power up The voltage was with the wires connected. The wires to the power switch are solid. The do not disconnect from the switch. The voltage of the green wire at the power plug with everything plugged in is .796v. The voltage on the back of the power switch on the front of the tower with everything plugged in is 4.75v.

10-07-2009, 02:26 PM	#14 (permalink)
wrench97 Moderator, Hardware Team Join Date: May 2008 Location: S.E. Pennsylvania Posts: 18,485 OS: Win7	Re: wont power up From the switch no from the motherboard is where you would disconnect them, however since you were able to get a reading from the switch wire of 4+ volts. It appears to bea power supply that's failed. __________________ Power Supply and Selection