HELP: New PC won't turn on + loud POP

[devi0us]

Hi guys, this is my 3rd pc ever built so I'm not exactly a greenhorn, but what happened last night has me stumped and troubled.

Firstly, a list of components:

MOBO: MSI K9AG Neo2-Digital AM2 AMD 690G HDMI ATX AMD

CPU: AMD Athlon 64 X2 4400+ Brisbane 2.3GHz 2 x 512KB L2 Cache Socket AM2 65W

PSU: OCZ StealthXStream OCZ600SXS ATX12V / EPS12V 600W

RAM: G.SKILL 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400)

HDD: Western Digital Caviar SE16 WD3200AAKS 320GB 7200 RPM 16MB Cache SATA 3.0Gb/s

Case: COOLER MASTER Centurion 534 RC-534-KKN2-GP

No GFX card because mobo has onboard (the PC is for my girlfriend).


I put the whole thing together last night with my girlfriends brother and when we tried to turn it on, nothing happened. "Okay" I think and go to press the button again. We hear the machine briefly turn on, fans whirring and all, and then turn off. I press the button again and this time, nothing happened except a loud POP like a cap gun, or electrical discharge from a Tesla coil. Then we smelled the horrid stench of burnt electronics.

We thought it was the PSU, so we quickly tested the new PC with an old PSU lying around. After the POP, with either PSU, after we tried to power on the PC, it most of the time NOT start up, but the Power LED in the front would blink. Sometimes the PC would powerup for a second then turn off.

We started dismantling the PC, piece by piece, testing each part to see what worked and didn't. We found that the RAM worked in another PC, and the new PSU powered up an old Pentium 4 PC that had no ram or HD in it (that PC gave two beeps on bootup though, must be the lack of ram or HD?). We couldn't test the CPU because her brothers Dell had a HSF that seemed to be soldered onto the mobo. We also couldn't test the HD or mobo.

I also tried to see if I did any wiring wrong, but I couldn't find anything out of place. Even if I did the power, reset, etc wires wrong, could it have done this much damage? Where'd the blow out happen and why? We were careful the whole time to look out for electro static discharge, so it couldn't have been that...

Right now we're looking at RMAing at LEAST the mobo. Any help/tips/pointers you guys could provide would be greatly appreciated.

 

[Slappy_Slime]

In a nut shell use the nose test, sense you already have the system taken apart. Smell for a strong burned smell on each part, motherboard/power supply/harddrives/etc. In other words run you nose across the circuit boards like a vacuum cleaner. And if it is the circuit, it will keep a strong oder for along while.....is you motherboard stand-off's in the correct place?

 

[cfvh600]

Also check for possible burn marks on the motherboard, and like Slappy_Slime suggested, follow your nose. Sorry to hear about the problems. Good luck.

 

[devi0us]

Thanks for the responses guys. I will check the mobo for damage and smell it up as soon as I can in a few days. Hopefully it will still retain the smell.

Also, excuse the noob question but what are the mobo standoffs?

 

[Uber_sven]

they are the brass risers which the mobo screws into and isolates it from the case. v important. in cheaper cases the risers are sometimes built into the case design themselves.

screwing mobo straight into case without risers is a big no-no.

from the sound of it your mobo is prob fried - happened to me recently when i tried to recycle an old socket A board which has been in storage for some time. its very distressing when it occurs !

 

[devi0us]

Oh my goodness... NO I did not use the brass risers... Aww man I knew I did something wrong. So wait, if the mobo touches the case like it did in this case then it can cause a short or worse? Man I messed up big time. =/

I don't think I can even make it work by using the risers because since there was a short, something had to have fried. Gahhhhhh...

 

[cfvh600]

yes if you didn't use the brass stand offs you definately caused a short which caused your board to pop. You'll probably see the place of the short on the bottom of the board when you take it out.

 

[devi0us]

I made a huge mistake, I guess I am a greenhorn after all. Thanks for your help guys. I'm gonna try to check all the components again to see what is or isn't damaged.