Bad MB????

[morabors]

I built this PC about 18mos. ago. About a year ago the video card and a single stick of memory went south at the same time. I thought there was something deeper wrong that caused the issue but just RMA'd those parts and did not have an issue until now. Now the PC does not boot/post at all. I get no beep at all during post and obviously no boot (used known good speaker). One of the fan headers is shot (replaced with a known good fan, no ggod). Another odd thing is the power button does not shut down the PC at all and the restart button does not function. I did swap the PS with a known good one with no change. I did remove all non-essentials from the USB headers, did pull memory hoping to hear error beep but still no beeps. I am leaning toward bad MB. I really want to avoid swapping CPUs unless absolutely needed. Do you guys have an opinion?
Thanks, specs below.

*Cooler Master RC-600-KKN1-GP Gladiator 600 Mid Tower Case - ATX, mATX,
*AMD Phenom II X2 550 Black Edition Dual Core Processor - 3.10GHz, Socket AM3, 6MB Cache, 2000MHz
*CORSAIR CMPSU-550VX 550W ATX12V V2.2 SLI Ready CrossFire Ready 80 PLUS Certified Active PFC
*LITE-ON Black 24X DVD+R 8X DVD+RW 12X DVD+R DL 24X DVD-R 6X DVD-RW 12X DVD-RAM 16X DVD-ROM 48X CD-R 32X CD-RW 48X CD-ROM 2MB Cache SATA 24X DVD Writer LightScribe Support
*GIGABYTE GA-770TA-UD3 AM3 AMD 770 SATA 6Gb/s USB 3.0 ATX AMD Motherboard SATA 3.0, USB 3.0, 3x USB power
*COOLER MASTER Hyper 212 Plus Intel Core i5 & Intel Core i7 compatible RR-B10-212P-G1 120mm "heatpipe direct contact" Long life sleeve CPU Cooler
*OCZ AMD Black Edition 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1600 (PC3 12800) Desktop Memory Model OCZ3BE1600C8LV4GK
*EVGA 9800 GT Video card
*SAMSUNG Spinpoint F3 HD502HJ 500GB 7200 RPM 16MB Cache SATA 3.0Gb/s 3.5" Internal Hard Drive -Bare Drive
*Arctic Silver 5 Thermal Compound

 

[ubercake]

Because you mentioned the power button won't shut down the PC and different components are failing on you one by one, it sounds like something wrong with the PSU. Corsair makes a good supply, but every good producer has a few fall between the cracks.

Those CMPSU-550VXs come with a 5-year warranty. If you have a power supply that fails to turn off when you hold down the power button, there is something seriously wrong. You could end up not only frying all your components, but also burning your house to the ground.

Contact Corsair and tell them how the power no longer shuts off when you hit the power button and they'll probably tell you not to turn on the PC again until they can get a new one out to you.

 

[morabors]

Thanks for the reply. I did swap the PS with a known good one and had the same situation, no post/boot and the power button did not work, that is why I rules out PS. I think I will give Corsair a call and see what they say but because a known good PSU does not change the situation. I guess it is possible that the PSU is bad and has blown the MB, what do you think?

 

[ubercake]

I guess with two power supplies and the same problem, you're right in thinking the motherboard. First inclination is always with the power supply when the power button on the case does not function.

 

[morabors]

Thanks, do you think it could be CPU or is that unlikely? Again, I an hoping to not have to swap CPUs unless absolutely necessary.

 

[jsc]

I would suspect motherboard before CPU. Although CPU's do fail, it's pretty rare.

 

[ubercake]

Honestly, I haven't run across too many times when a CPU has been the culprit. A replacement motherboard will run around USD $90 if it's not still under warranty.

 

[morabors]

Again, I appreciate the responses. I was hoping that you guys would help me with 1 last thing if you can. In an attempt to feel confident the PSU is not the issue I have tested it in I believe a manner as laid out in this forum, PSU plugged in but not powered and then powered on. The following are my results, are you guys able to review and confirm these are correct?
Switch off
Green 3.51
Gray 0.00
Purple 5.14
Switch on
Green 0.02
Gray 5.11
Purple 5.14

No voltage on Orange, Red or yellow with switch off. With switch on they are:
Orange 3.36
Red 5.10
Yellow 12.10

I also breadboarded the MB with no change to status. This was MB out of case, power connectors connected, 1 stick of mem (and then with no memory at all) and the MB speaker. Got no beeps at all.

 

[morabors]

Just wanted to update with the solution. It was indeed a bad Gigabyte MB. I sent it back for warrenty with no bent corners. Gigabyte refused warrebty due to a bent corner. I strongly suspect they bent the corner to avoid warranry work. I purcgased a ASUS to replace the Gigabyte. Thanks

 

[marbski]

it's your motherboard is defected, try to ask a pc technician on that..