No Power, No Power, No Power

Need help troubleshooting a power failure.

Store bought HP p6130y, no upgrades or mods. Windows 7 (vista Upgraded), AMD Phenom X4 9750, 8g DDR2, GeForce 9100 Integrated. MB is a Pegatron (Asus) M2n78-LA, PS is LiteOn 300W. System is about 8-9 months old.

About a month ago, I started seeing some sluggish graphics. For instance, if I minimize or maximize the Firefox window, it slowly expands or shrunk. Also, videos (windows media player, youtube, Winamp, all of them) played with extremely low framerates and would eventually freeze the entire system, requiring a re-boot. I ran a utility program, and all cpu & memory usage was reasonable. In addition, there were no problems with Download speed, or processing (Burning dvd's for instance). The slow issue seemed to be only graphics related. I DL'd the latest Nvidia drivers, but didn't help.

The other day, I had computer on for about 15 minutes, walked away and came back 15 minutes later, and it was powered down. Pressing power switch did nothing. I unplugged, waited, then re-plugged, and when I pressed power switch, the fans would run for about a half second and then no power. Seemed like a circuit breaker on the PS.

I've seen the No-Power checklist here, and have followed as closely as possible, although because I did not build it myself, I couldn't follow it 100%.

Here's what I have found out:
PS works on it's own with Paperclip test.
System does exact same thing - 1/2 second then shutdown, with 2 other working power supplies (a 300w and a 250w).
Disconnecting the power switch from the board, and jumping the posts on the board cause the same 1/2 second of fan power.
MB shows no Visible signs of damage or burnout. All capacitors look ok Visually.
I removed and reinstalled CMOS battery.
Removed all memory sticks, and tried powering up with 1 at a time with no luck.
I tested the Power Supply (but not under load) with these results -
All red wires were +5.11 volts
All Orange wires +3.40 volts
All Yellow wires +11.98 volts
Violet wire +5.09 volts
Blue wire -12.00 volts
Grey is +4.70 while at power

I have read here that the grey wire needs to be tested under load, as switch is turned on. I have not tested that or any other wires under load yet, cuz I don't know how. Should I strip insulation off the wires so that I can have a place to probe them?

I have tried to research this as much as I can, so I don't waste anyones valuable time. I have seen numerous threads regarding the subject, and have tried to follow all instructions that I can.
This problem seems to be related to the MB and the integrated graphics. Don't know what else to test, or how to determine if it's the MB or CPU. The board does have a speaker, but it doesn't buzz or click at all during this process.

I appreciate any and all help. I am not trained or experienced in electronics testing, but can follow instructions well. Thanks!

btw, this sucks extra because of the newness of this system. I've had other computers last 8-10 years with no hardware failures. Curses!!!
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  1. Have you contacted HP? Your description sounds like an internal short or other malfunction on the motherboard.
  2. Well that's silly of me, it has a 1 year warranty. For some reason, I thought it was 90 days.

    I guess I should just call HP and let them take care of it.
  3. I was about to bring the warranty up.

    I think its a bad PSU. But its their problem.
  4. Thanks for reminding me about warranty. I have never in my life had anything replaced under warranty, and just assumed that this wouldn't be covered.

    And, here I am with a freaking multimeter trying to figure out power-on voltages, when all I had to do was call an 800 number.

    So, I just got off the phone. It was tedious because they had me run through a bunch of tests I've already done, but I didn't want to let on that I've gone a bit further. Got connected to a tier 2 guy who thinks it's the MB, which is what I suspected. So, they send me a box with prepaid postage, and I live without that computer for 2 weeks. Works for me.

    Thanks anyways!
  5. They are just sending you the board?

    I thought they would send a tech or swap the whole system.
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