I have been building my own system. After reading the forums there doesn't seem to be a problem exactly like mine. Please understand I am a 21 year old who knows software and programs, but that my knowledge of bulding computers&troubleshooting has just come from reading "how-to" guides, fidgeting with these parts for a week, reading forums, and talking to 2 knowledgable friends.
For starters, here are the parts I have purchased:
My first run through of the system worked well. I had every component seated and plugged in correctly, with the exception of the gpu. The graphics card was in the box. I figured: "because the gpu usually requires the most drivers and installations, i will sort it out after i get my system working first."
I fire up the system for the first time. I get the bios screen, read around for a while, then shut the computer off. Great. Next, i insert my dvd image of windows 7 64bit while the computer is off. I turn on the computer, it recognizes the windows 7 installation disk. Great. I install windows 7 perfectly. I get to the home screen and begin installing the drivers and utilities included with the motherboard from the cd included with the motherboard. This all works flawlessly.
With the system working well as expected, I finish installing some motherboard and bios drivers/updates, and shut the computer off. I wait a few minutes and sever the power supply from the wall. I thought now would be an appropriate time to put the gpu in the motherboard. I push the gpu in to the main pci-e x16 slot (with much more force than i thought would be necessary, the motherboard bending), plug in the two 6pin cables from the power supply to give my gpu power. I plug these in snugly, plug in the power supply to the wall completely, wait, and then fire up my system again.
Failure. On my motherboard there are 4 LEDs in the upper right next to the HDMI output and also 2 LEDs on the bottom left just below the SATA 2.0 plugs. These LEDs flash for a second and then go blank. Also, the two case fans, power supply fan, and the cpu fan spin for about 2 seconds, and then stop spinning. All fans stop working at the same time. I do not receive any image on the monitor. The monitor acts as if i did not power up the computer at all.
My initial thought: "un-do the change that made the system not work." I unplug the gpu from the computer completely and place it on my wooden kitchen table. I push power. Nothing happens (except the top LED, which is bright).
I remove power and disconnect the SATA cable from the CD drive (it is now just a piece of metal sitting there), and try the system. Nothing (except the top LED, which is bright).
I remove power and disconnect the SATA cable from the hard drive (now reduced to an object sitting there doing nothing), and try the system. Nothing (except the top LED, which is bright).
I take out both sticks of RAM, and power up, nothing. (I was told the computer will go in to the bios without RAM, correct?) Side note for RAM installation: as a first time builder, I did not expect to have to push the RAM as hard as I did to get it to "click" in the slots. I seriously thought I might be breaking it (and flexing the motherboard the in process).
My computer now consists of a power supply connected to a motherboard+cpu with no memory in it. The case fans are disconnected. I unmount the motherboard from the case completely and place it on the kitchen table. I disconnect all cables from the motherboard. I effectively start over.
As it turns out, subsequent constructions of a computer take about 1/5 the amount of time as the first build. Armed with knowledge and experience I start from the beginning again, being extra careful and meticulous.
The computer doesn't start, with many combinations of components tried. Throughout all this, however, the top LED stays bright.
With all components (except gpu) in place and the system off, I try to reset the cmos. According to my trusty motherboard manual ( http://www.biostar.com.tw/app/en/mb/introduction.php?S_... ) taking a cap off of pins 1&2 of a three pin setup and placing it on pins 2&3 should do the trick. I place the cap on 2&3, wait 10 seconds, and place the cap back on pins 1&2. Push the power button, no go.
I'm out of ideas. I've tried all logic and manual suggestions that I can think of. I can continually get the "power LEDs" on the front of the case to light up bright blue, yet none of the LEDs on the motherboard even blink and the fans won't spin. The power LEDs go from the LED itself to the post on the bottom of the motherboard to the right of the front USB connections. I've even tried messing around with the power switch/reset switch/power LEDs positioning among that 16 pin bank to no avail.
I read lots of reviews for motherboards, the one i picked has a lot of features (USB3, SATA3, HDMI, 2 pci-e, 4 mem slots) for a great price ($90) and biostar seemed like a reputable brand based on everyone's comments.
I agree that the problem would seem to be the power supply, but that one LED on the front of the Antec 300 shines bright every time, it gives me hope that the power supply is working. And that LED is connected to the motherboard...so this means the motherboard is drawing power from the 20+4 plug, and that power is flowing all the way down to the pins for the LED. I'll try to get another power supply to test.