Can't turn computer on after installing everything

[darkbunny]

I just built my first computer using:

Core i5 750
Asus P7P55D mobo
Radeon 5770
This ram: http://www.newegg.com/Product/Product.aspx?Item=N82E16820231193&cm_re=g_skill-_-20-231-193-_-Product
Cooler Master Elite 460 PSU
Cooler Master HAF 922
Western Digital Caviar Green 640

Now, I have everything installed on my motherboard, and it's all mounted in my case. When I plug the power cable into my psu and the wall, I get the green standby light on my motherboard, but when I try to turn it on nothing happens. Since this is my first build, I really don't know what the problem is, and as far as I can tell the case didn't come with the system speaker so I don't really know how to diagnose the problem on my own. Initially I thought I just plugged some cables in wrong so I uninstalled all of them and then reinstalled them all. Still nothing. So then I thought that maybe I just needed to get a new (more powerful) PSU (and that's still sort of what I'm thinking.) None of the warning LEDs on the mobo are lighting up, just the standby one, and it's a consistent green after I flip the switch on the PSU.

Any help would be greatly appreciated.

 

[darkbunny]

Ok, after going the breadboarding process and discovering my case does in fact come with a system speaker, I still don't know what's wrong. I have just the cpu and heatsink installed, and the speaker is in (but I'm not sure if correctly, it should just connect to the same pin device as the power/reset/etc. mobo connector right?)

Anyway, after going through this, it does boot (again, with just the cpu and heatsink) but now the red led light by the cpu comes on and I get no sound from my system speaker, although it does sound like something is coming from it, not sure if it's just because I'm giving power to the motherboard and it's getting turned on or if it's broken or something.

 

[Paperdoc]

How do you now it boots? Do you have the video output connected to your monitor to see the POST messages? What do they say?

Normally a minimal breadboard starts with ONE stick of RAM in place so the machine can complete the POST and get to the point of trying to find a drive to load an OS from. If it gets that far, you should hear one beep signaling that the POST itself completed successfully.

 

[shortstuff_mt]

READ before posting about boot/no video problems!

Let us know how it goes after you've performed EVERY step in the above checklist.

 

[darkbunny]

Alright, here's how far I've gotten:

Went through the guide, checked off everything. After figuring out that I had accidentally flipped the GFI circuit on my PSU earlier and also my heatsink was installed incorrectly so I fixed those issues when I was breadboarding. Anyway, I got the RAM to install correctly, the beeps told me I needed to put in my video card, installed it, powered it, and then it gave me the one beep to let me know it had POSTed. I plugged the monitor into the card while it was still not installed in the case just to make sure it really was on and everything was fine, but then as soon as I re-mounted the motherboard and PSU into my case, nothing, once again. Since I was able to get it to POST outside the case and I currently have tested it several times with none of the chassis cables connected to the PSU, I'm really at a loss about what to do. I obviously can't just leave it outside the case.

 

[shortstuff_mt]

That indicates a short. Make sure you don't have any extra standoffs installed that don't line up with a hole in the motherboard. Also make sure no metal tabs are getting into the rear-panel connectors causing a short.

 

[darkbunny]

I think that was the problem. There was a plug that I had in which after removing seemed to solve the problem, as I'm now posting this from my new machine, quite happily.