Building a computer. Need help!
 

Here are the specs:
Albatron socket 775 mobo PX915P/G series
Pent. VI Prescott 3.2 ghz hyperthreaded cpu
2 sticks of pqi 512mb pc4000 DDR RAM
Seagate SATA 200gb HDD
ATI X600 256mb PCIEx16 gfx card
Samsung DVD/RW drive and Samsung DVD/CDR drive
RAIDMAX 420W power supply

I'm builidng this computer for my sister, and got the parts from newegg.com. While it's been 1 1/2 years since I last built a computer, I got her all slapped together and powered her up. It goes through POST and once it gets to the boot from CD option, it shuts off after a few seconds. At first I thought it might be the HDD, since I had never installed a SATA or really know how they work, so I swapped it out for a Maxtor IDE drive. I managed to get into Windows setup while it scans devices before it shuts off. Now I'm starting to think that the power supply is the problem. The motherboard has a 24 pin power connector on it, and the power supply has a 20 pin plug. However, I'm using a 20 pin to 24 pin adapter. I don't want to jump to conclusions though, so I thought it best to ask here for help. Thanks.

You're probably right. My first impresssion is that what you've got in the case is going to require quite a bit of power.

If you wanted to know for sure, couldn't you just disconnect all the non-essential stuff and try again?

Good luck

Unless it's a no-name crappy power supply, your 420 watts is more than enough to power the computer. I've seen similar systems run on a high-quality 300 watt PSU... The little I've seen of Raidmax shows they're occasionally (?) using Antec cases, which are high-quality. It is therefore a bit unlikely that the PSU is crap.

However, the PSU could be defective, so perhaps you could try getting a replacement somewhere...

By the way: it could be the CPU temperature instead - if the cooler isn't installed properly, the temperature goes up and up and up, until the computer shuts itself down to protect it.

Another option is the memory: try putting in one of the two dimms, see if that solves it. Or run a program called Memtest86 to check them for errors (use one dimm at a time!).

Drop into the bios and watch the cpu temp... see if it keeps goin up...sounds a lot like a heat prob... check that heatsink... if thats all good....

then try the memtest86 like Dragonlich mentioned... http://www.memtest86.com/

I think I owe you two handjobs. I checked the temperature in BIOS and the cpu was at a nice, toasty 93C. I pulled the fan/heatsink off then I put it back on FIRMLY this time, and now it's running at 73C, and working properly. Thanks a ton!

Edit: Maybe I spoke too soon. After messing with it a bit more, I managed to get the cpu temp. down to 55C, and managed to install WinXP. However, it has been freezing on me, and when I restart, all it does is give me one long, drawn out beep. I'm not that up on my beeping knowledge, basically, I know is one short beep is good, two short beeps mean memory problem. I'm about at the end of my limit with this fucking hunk of shit, and I really want to just toss it out the fucking window.

chip could be heat-damaged now, it's happened to me.
in my experience, once a chip has been at super-hot temps (due to a lack of or improperly-seated heatsink), it can sometimes only survive at unsustainably low temps without locking. It sucks, but you might be able to rma the cpu and try again. I have had that exact experience with installing and locking in this situation.
Either that, or incompatible memory. Some brands don't work with some boards. Some people might say 'bad ram', but it's really just incompatible.

One problem down, many to go, it seems... :)

I have only myself to blame, really. All this new stuff I've never worked with before, and I assumed a little too much maybe. Oh well.

newegg usually has a really good RMA policy. Send the CPU back for a new one.

Also, check ram speeds and timings.

Just thought I'd give an update. The computer is up and running now with no problems. I'm not sure why, but initially after I had installed XP on it, I was putting the gfx drivers on from the cd when it froze. I was pretty pissed off at this point because of the numerous times it had been freezing on me before, so I basically said fuck it. A couple days later, I got some arctic silver thermal paste for the cpu, then I simply reinstalled XP, and d/led the gfx drivers off the net. I put it through some paces with a couple games, and it's working fine. Thanks to everyone for the help, especially suggesting checking the cpu temperature.

Were you using any thermal paste at all the first time around? If so, what kind? If not, you should be flogged, which, I suppose, you sorta were.

I was using the thermal pad that came with the fan/heat sink. I had to wipe it off to read the numbers on the processor to a techie at Intel.

I've nevre used a thermal pad since I always have a tube of Arctic Silver 3 around, but I've heard they're not very good.