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M4A79 Wont Boot

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December 7, 2010 1:24:06 AM

I've been running an M4A79 Deluxe for over a year now. I decided to upgrade to an SSD using an Asus U3S6 pci-e controller for SATA3. I installed the card and hard drive and now my pc wont boot. The motherboard seems to get power (both the onboard reset and power buttons light up) but nothing happens when I try to cut on the computer. The lights are on but the motherboard acts like it gets no power.

So far I've done the following:
-Removed add on card and tried original configuration
-Reseated Ram, Processor, All PCI Cards
-I've double checked the 24 pin and the 8 pin cables going to the motherboard.
-I've tried to clear the CMOS on the motherboard but cant even get it to boot to do this.
-Disconnected power switch and tried using the button the motherboard.
-Removed Motherboard battery trying to clear it

My specs are as Follows
Asus M4A79 Deluxe AM2+ Motherboard
8 Gigs G. Skill DDR2 Ram
Radeon 5850 Video Card
2 hard Drives (Seagate / Western Digital)
2 DVD RW Drives
1 Blu Ray Drive
Hauppauge PCI TV Card
Thermaltake Toughpower 750 Watt 80+ Certified PSU
Antec 1200 Case

New Parts
Crucial C300 SSD
Asus U3S6 PCI-E Controller Card

I've been building computers for nearly 20 years and this one has me at a loss for words. Symptoms seem to be a bad power supply or motherboard, but both had been working great up until the upgrade.

More about : m4a79 wont boot

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a b V Motherboard
December 7, 2010 6:39:16 AM

Your specs show your psu can handle anything you throw at it(provided its under 800W :)  )

breadboard the innards and only use the essentials for booting e'g boot drive,1 stick of ram, mobo, gpu and see if you get any message/display on screen.
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a b Ĉ ASUS
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December 7, 2010 1:36:03 PM

Work 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.

I have tested the following beep patterns on Gigabyte, eVGA, and ECS motherboards. Other BIOS' may be different.

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 or long single beeps indicate a problem with the memory.

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.
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December 7, 2010 11:27:14 PM

Thanks for the advice. I figured I'd have to "breadboard" but was trying to avoid it. Went ahead and did it and got nothing.

After dismantling everything and still getting nothing I bought a new PSU to test and everything booted right up. I guess a thermaltake Toughpower 750 isnt as tough as they say. 2 years and it gives out with no warning. I think its still under warranty, anyone had any experience with thermaltake honoring there warrantys?

Thanks to everyone who replied and gave advice.
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a b Ĉ ASUS
a b V Motherboard
December 8, 2010 5:24:01 AM

I got mine replaced instantly...
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December 10, 2010 6:41:03 PM

So far thermaltakes warranty service seems to be top notch. They no longer make my exact model so they are mailing me a more current 850 watt one instead. Hopefully I'll have it next week.
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December 18, 2010 1:15:13 AM

Thermaltake was great about honoring there warranty. Took them less than a week to mail me a new power supply. Its up and running perfectly. Thanks for all the advice offered from the people who responded.
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a b Ĉ ASUS
a b V Motherboard
December 18, 2010 3:26:43 PM

Hey, we're here to help! :0
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