Problem powering on the computer

Sorry if this question is in the wrong place. I recently put together a computer but I am having problems turning it on. The "power" button on the front will not work right away. I have to turn off the power supply switch for about a minute and then turn it back on, then the power button on front of the case will turn on the system. I called the place where I got the motherboard and they told me it could be the power supply. I just wanted to get some opinions before I have to spend money on a new power supply and finding out it is something else like the motherboard.

Here is my computer's setup. I have a 400 watt power supply (I forgot the brand but something like EnerSomething), Asus A7N8X motherboard with an AMD 2100+ processor, Asus 8x GeForce Ti 4200 video card, Pioneer Dvd drive, Pioneer DVD-RW drive, Sony CD-RW, floppy drive, 2 512meg sticks of PC2700 memory, Western Digital 100gig HD, Coolermaster HD bay cooler, Vantec CPU fan, 2 case fans plugged into the motherboard, 2 lighted fans plugged directly to the power supply.

Hope that information helps. If this is a real stupid question, I'm sorry, I guess I'm just a real stupid person. I appreciate any and all feedback that you have to offer. Thanks.