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Computer not booting

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March 13, 2011 3:53:16 AM

EDIT**
I have read the 'first boot' guide and it really helped me on my build. I also read it several times now that my desktop stopped working. I'd like you to give me the benefit of the doubt that I've done my research. Thank you =)

Computer makes no sound at all when trying to power up.

I built it four months ago and it ran perfectly the first time but then I unplugged everything and put the case back in the box with the components inside.
On Christmas, I took it out and booted it just fine, and played to my heart's content for a month. Put the case back again in the box and left.
Spring Break, I come back missing my bastard child and it just won't wake up. =(

Won't boot at all, no sounds, no beeps, no fans turning, no earth shaking, NOTHING.
Only thing I can hear, because I was extra paranoid, is a very low chirping sound coming from the PSU when I turn it on. It sounds electrical in nature, but then again, I can't be sure it wasn't there in the beginning, since it's VERY low.

MOBO: Asus P7H55 USB3
CPU: i5 750 2.66 GHz
GPU: GTX460 1GB EVGA
RAM: 2x2 GB ADATA Gaming Series
PSU: Thermaltake TR2 RX 850W
OS: W7 Ultimate 64bit
Case: Antec 300

Anything else shouldn't matter since...
Things I did:
1. Came home, took out the case, plugged peripherals, plugged PSU, turned it on, pressed Power Button on case. Nothing
2. (I always power off and unplug, and the MOBO's LED is at least on, also, the Turbo Key turns on a red light)
3. Opened case, tried shorting the power button with flat screwdriver and clip. Nothing
4. Took out PSU and connected Green to Black with clip, PSU fan works.
5. Connected PSU to a fan and tried the Green/Black clip thing; both fans work.
6. Tried Breadboarding or benchtesting (Hope they're the same, LOL)
7. Connected PSU to MOBO and added a RAM stick; used case Button and Shorted; nothing.
8. Added GPU, connected to PSU, tried to power it on both ways. Nothing.
9. (Yes, the 4 pin was always in when I tried to turn it on, as well as the 24 pin thing.)

Help me help you help me =(

More about : computer booting

a c 90 B Homebuilt system
March 13, 2011 4:20:43 AM

Hello kradreyals;

Let it sit with the power plug attached to the wall for a while.
See if the CMOS battery will take a charge and if that might not fix the boot problem.
March 13, 2011 4:59:29 AM

Define a while. xD
Anyway, it has been able to boot at another time when I left it for a month and a half. Thing is, I unplug everything every time I leave for college. Is that a bad thing to do?

Also, my PSU is a thermaltake 850W. The motherboard's LED light turns on when I turn 'flip' the switch on the back of the case. I'm starting to get worried. =(\

Edit: Just test my PSU with the 'green to black paper clip' method and it works just fine. Help =(
Related resources
a c 122 B Homebuilt system
March 13, 2011 5:48:48 PM

Work systematically through our standard checklist and troubleshooting thread:
http://www.tomshardware.com/forum/261145-31-read-postin...
I mean work through, not just read over it. We spent a lot of time on this. It should find most of the problems.

If not, continue.
The following is an expansion of my troubleshooting tips in the breadboarding link in the "Cannot boot" thread.

I have tested the following beep patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different, but they all use a single short beep for a successful POST.

Breadboard - that will help isolate any kind of case problem you might have.
http://www.tomshardware.com/forum/262730-31-breadboardi...

Breadboard with just motherboard, CPU & HSF, case speaker, and PSU.

Make sure you plug the CPU power cable in. The system will not boot without it.

I always breadboard a new build. It takes only a few minutes, and you know you are putting good parts in the case once you are finished.

You can turn on the PC by momentarily shorting the two pins that the case power switch goes to. You should hear a series of long, single beeps indicating memory problems. Silence indicates a problem with (in most likely order) the PSU, motherboard, or CPU. Remember, at this time, you do not have a graphics card installed so the load on your PSU will be reduced.

If no beeps:
Running fans and drives and motherboard LED's do not necessarily indicate a good PSU. In the absence of a single short beep, they also do not indicate that the system is booting.

At this point, you can sort of check the PSU. Try to borrow a known good PSU of around 550 - 600 watts. That will power just about any system with a single GPU. If you cannot do that, use a DMM to measure the voltages. Measure between the colored wires and either chassis ground or the black wires. Yellow wires should be 12 volts. Red wires: +5 volts, orange wires: +3.3 volts, blue wire : -12 volts, violet wire: 5 volts always on. Tolerances are +/- 5% except for the -12 volts which is +/- 10%.

The gray wire is really important. It should go from 0 to +5 volts when you turn the PSU on with the case switch. CPU needs this signal to boot.

You can turn on the PSU by completely disconnecting the PSU and using a paperclip or jumper wire to short the green wire to one of the neighboring black wires.
http://www.youtube.com/watch?v=5FWXgQSokF4&feature=yout...

A way that might be easier is to use the main power plug. Working from the back of the plug where the wires come out, use a bare paperclip to short between the green wire and one of the neighboring black wires. That will do the same thing with an installed PSU. It is also an easy way to bypass a questionable case power switch.

This checks the PSU under no load conditions, so it is not completely reliable. But if it can not pass this, it is dead. Then repeat the checks with the PSU plugged into the computer to put a load on the PSU.

If the system beeps:
If it looks like the PSU is good, install a memory stick. Boot. Beep pattern should change to one long and several short beeps indicating a missing graphics card.

Silence, long single beeps, or series of short beeps indicate a problem with the memory. If you get short beeps verify that the memory is in the appropriate motherboard slots.

Insert the video card and connect any necessary PCIe power connectors. Boot. At this point, the system should POST successfully (a single short beep). Notice that you do not need keyboard, mouse, monitor, or drives to successfully POST.
At this point, if the system doesn't work, it's either the video card or an inadequate PSU. Or rarely - the motherboard's PCIe interface.

Now start connecting the rest of the devices starting with the monitor, then keyboard and mouse, then the rest of the devices, testing after each step. It's possible that you can pass the POST with a defective video card. The POST routines can only check the video interface. It cannot check the internal parts of the video card.
a c 113 B Homebuilt system
March 13, 2011 7:22:49 PM

You have a lot of great advice already, but I'll contribute my guess since you asked.

It sounds as if the power coming from the PSU is no longer accepted by the MB.

-This could be because the PSU is damaged or faulty. Other Thermaltake TR2 RX units were made by HEC, a rather crappy PSU OEM usually. Maybe this one was as well... I have no solid info and in my opinion Tt can be very shifty when it comes to models and such.

-Or it could be the MB itself should be accepting the power but is not because of failure.

A PSU that can run a fan and appear to start when jumped is not always a working PSU. A fan can run with a wide spectrum of DC power, but a CPU needs very precise power. The various rails could be tested for voltage with a multi-meter, but even that doesn't rule out more transient issues that the meter is not sensitive enough to record.

You probably need to swap in a known working PSU, then if that's not it replace the MB.

March 13, 2011 10:35:56 PM

Alright, since I couldn't figure out which one wasn't working and I do not have a known working PSU, I went Best Buy (Yes, probably not the best choice) with my MB and PSU for them to test them but apparently they want me to reassemble my whole computer after I stripped it down for testing.

Do you guys have any recommendation as to where to go? Or should I bother reassembling my whole computer just so they'll eventually strip it down to the PSU and the MB xD.

Thanks. =)
!