Strange Power Problem?

[jpmower]

I recently built my first computer, everything seemed to work fine. The first few times I powered on it worked but the third or fourth time when i pushed the power button nothing happened, after waiting a while it would power on again. The next time i tried it, it worked but the time after it didnt. Sometimes i can faintly hear one of the fans try to spin but nothing happens. Basically my problem is that my computer will only power up about half of the time i try. Any suggestions on why this is happening or possilbe solutions? any info would be greatly appreciated. Thanks!

[not important]

Are the Power wires connected firmly onto the MOBO? I have seen the Power buttons get pushed back into the case front.

[MakeYourslf2012]

What kind of unit is it? What are your full system specs?

It could also be a failing PSU.

[jpmower]

I've tried reconnecting the case's power wires to the mobo but no luck, would it be wise of me to buy a new power supply to try, or are there other options i should try first? I really appreciate the help! Thanks!
I'm pretty new to this so I'm not sure if this is the "full" specs but it is a p4 2.0 ghz 478 cpu, Shuttle av49pn mobo, Echo Star 450-Watt 20-pin ATX PSU, AVC Socket 478 Heat Sink and Fan up to 2.8GH, VGA EVGA MX4000 DDR 128, 512MB PQI 184P DDR SDRAM, 120 GB Seagate Internal HDD, Win XP Home SP2,

[Cricket]

Originally Posted by jpmower would it be wise of me to buy a new power supply to try, or are there other options i should try first?

If you can't borrow a P4 compatible power supply from someone then buying a new one is really your only option. But I would definitely replace that Echo Star power supply.

Cricket

[jpmower]

Well I tried a different power supply and it worked so that must be the problem, guess I'll buy a better one! Thanks everyone for your help, I really appreciate it.