My computer (First boot) Turned on, but then shut off a split second before, then did it again without me touching the power button again. All the fans spun up, everything seemed to work, but then it shut off. Using the process of elimination I have narrowed the problem down to the Motherboard, the PSU, and the CPU, (I one by one disconected each thing, graphics card, even the ram, untill I was left with these three core components. One of them has a problem.) I personally think the PSU just crapped out. What do you guys think?
That "problem" is usually just the motherboard failing to POST and re-trying with different settings. You need to list your complete system specs. You should also go through EVERY step in this checklist:
The checklist was created to troubleshoot problems exactly like yours.
I don't mean to doubt you, but most people coming here asking for help SAY they went through the checklist. Few people actually have performed every step in the checklist. Did you perform the breadboarding step where you build the system with the motherboard outside the case on a non-conductive surface to rule out a short? Do you have a system speaker installed so you can hear any BIOS beeps?
It's really hard to help when you don't list your complete system specs.
Your right that I didn't do EVERYTHINg, but yes, I did try out the motherboard on a cardboard box outside of the computer, but no, I don't have a speaker. My Antec 900 didn't come with one, or I just didn't find the speaker cable. I tried reversing some of the frontpanel connectors, removing all non necessary hardware, I cleared CMOS, and I have checked and rechecked ALL connections (by means of reseating everything) at least 3 times. At this point, I feel I have tried pretty much everything, and that is why I am coming to the forums.
I have a similar problem, where the computer would power on for a few seconds then power off. I RMA'd my power supply and will try it with a new on. Then if the problem persists I am going to try to take the power cord off the motherboard and try powering the system on with a screwdriver. If you touch the metal pins with a metal object it will start the computer. This will see if the case has a bad power cord. If that is not the problem I would think I have a bad Motherboard and so should you in your case since we seem to have the same problem, hope this helps.
I just thought of another reason for a computer to go on and off as you described. If the power button is permanently shorted due to the button getting stuck in or other fault then it will cause the computer to go on and off. Try disconnecting the power on lead and starting by temporarily shorting the power on pins with a screwdriver.
I have Antec 900 cases. And yes, they do not come with system (sometimes called "case") speakers. Having said that, if you have an Antec case and your build doesn't work, you really, REALLY, REALLY need the case speaker.
At almost every step of troubleshooting, just the presence or absence of sound is going to point you one way or another. Without the case speaker, you do not have a clue of what is going on and you have limited yourself to blindly changing components. And if you have two bad components ...
This is why I always point out the missing speaker when I read that someone is contemplating using an Antec case.
And the simplest way to verify that the case power switch is working is to swap it with the reset switch and try to boot with the reset switch - also in the checklist.
And please post system specs.
I don't like repeating steps that I've already put so much time into putting in the checklist, but here it goes:
#2 on the checklist is by far the most common mistake. Are you sure the 4/8-pin CPU power connector located on the upper edge of the motherboard near the CPU socket is fully plugged in?
Did you carefully follow the instructions on how to install the HSF? Is the HSF tight with little to no wiggle room? It doesn't take long for the CPU to overheat and shut down the system if the HSF isn't installed correctly.
Are you sure the CPU is installed fully in the socket and in the right direction? Were there any bent pins in the CPU socket on the motherboard?
Did you try each stick of RAM by itself and are you absolutely sure you're using the correct RAM slots?
Like jsc said, there's really no way of telling what the problem is without a $2 system speaker. They're worth their weight in gold in a situation like yours. I HIGHLY recommend getting a system speaker unless you want to randomly start replacing perfectly fine components like a lot of other people.
Do you happen to have a PSU from another computer that you can try? You can't put much weight behind Newegg reviews, but one reviewer of your PSU on Newegg said they solved a similar problem by using a different PSU.