problems building a computer :(

hey guys,
i recently bought a seperate case, motherboard, graphics card, etc; the works. after i plugged everything where it's supposed to go, screwed everything in it's place and all, i got a few problems:

1. when i start up the computer and go into the bios, it doesn't detect any IDE devices; master or slave.

2. sometimes i get an error message saying that my cpu fan speed is low (when i check it in the bios, my warning speed for the cpu fan is 1200, and my cpu fan spins around at 1100-1400 rpms average, but span at around 3300 once.)

3. my computer turns off out of nowhere while in bios SOMETIMES.

here's my setup:

Asus A8N-SLI Deluxe
AMD Athlon64 X2 3800+, S939
Kingston Dual Channel DDR PC3200 RAM 400mhz
XFX 7600GT XXX Edition
Maxtor 160GB IDE
Ultra 500watt PSU

so basically, i start

that's all that i remember for now. i'm currently not at home next to all the parts, but i will try anything that you guys can recommend. thanks.

whoops.

"so basically, i start"

meant to say

"so basically, i start up the system and wait for my OS to start. i get a disk boot failure if i wait long enough, so i go into bios. inside my bios, none of my IDE components are detected. hard drive or cd-drive. so i exit and try reconnecting cables and try again. now i'm stuck."

BUTTS

sounds like you have insufficient power to run the system.  either that, or you fail utterly at plugging tab a into slot b.

maybe your power supply is switched to the wrong species of house current.  if you've got a stupid looking switch on the back to select voltage, make sure it's set to 115 (primarily american) or 230 (primarily anywhere else).

i don't think it's power supply. i immediately thought that it was that as well, but all the plugs are in their correct position (even checked the manual) and yes, the switch is set to 115v.
its running fine now, no power failures or anything like that, but it still wont detect any IDE components.

possibly faulty hardware then.  i'll assume you know how to jumper your drives correctly, aren't trying to plug cables in backwards, and have bios set to autodetect drives.  just try attaching them one at a time as masters and see if you can detect either of them that way.

got it to work. don't know how, don't know why.
just unplugged everything, and reconnected it, piece by piece.
booted up just fine and installing windows xp sp2 right now. thanks for the comments anyway.

"got it to work. don't know how, don't know why.
just unplugged everything, and reconnected it, piece by piece."

   It's unreal how often a bad cable or even a power cord can cause shit like this. Grab some new ones and always keep spares.

sigh... i'm back again.
now i have an even more frustrating problem.
here's how it went:
last night, i got the computer up and running, installed my OS, installed chipset, etc. i left it on overnight playing music, turned it off in the morning, went to school, came back, and turned it back on to install some programs. now, i had to go to work right after i got out of school today, so i left my computer on while it was installing a game. when i came back from work (which was only a short 3 hours) my computer was off. when i tried to turn it on, it powered up for about 3 seconds, and shut off. however, the light on the motherboard indicated that there was still power running through it, and every time i tried to press my power button, it would not work. i switched my psu off, and the light turned off. i switched the psu back on, and after about 1 second, the computer started up by itself again, only to shut down after about 3 seconds.

i've tried practically everything /comp/, please help me with this ordeal.

   Since you assembled it I trust you removed the celophane on the heatsink interface with the cpu? Since it shut down while you were at work I suspect some sort of overheating. The game install at worst might have forced a reboot, not a shutdown.

yeah, i also suspected an overheating as well, although everything seemed like it would be cool enough. i ran some stress tests the night that i installed and also ran speedfan, and the temperatures  seemed fine enough. perhaps something might be wrong with the motherboard? i tried the motherboard with other psu's, with nothing else connected besides (the fan/processor) and it still did the boot-up shutdown.

yeah, i also suspected an overheating as well, although everything seemed like it would be cool enough. i ran some stress tests the night that i installed and also ran speedfan, and the temperatures  seemed fine enough. perhaps something might be wrong with the motherboard? i tried the motherboard with other psu's, with nothing else connected besides (the fan/processor) and it still did the boot-up shutdown.

   Might be the mobo but if it ran originally I'd sort of doubt that. Can you RMA it?