Humidity is unlikely to cause you a problem, very low humidty can be an issue, if nothing else there's a higher risk of static buildup.
Power supplies can be a worry. The specs are as dodgy as all hell. There's no way you can get 300 watts out of 98% of the 300 watt power supplies. Even taking that into account the components and general construction leaves a lot to be desired.
I'b be thinking to invest a=in a decent mains filter, don;t really need the expense of a UPS, just something to make certain no nasty spikes get into the computer and past the cheapo powers supplies.

> Does anyone have any experience with a crashing computer?

Does anyone here use the Windows operating system by Microsoft? ;-)

Sorry, I couldn’t resist. Without knowing more about your computer its hard to say. If you didn’t add any hardware then there is no reason to get a larger power supply. Did you add a Pinnacle Deluxe capture card by any chance? I had a Dell once (just once) that had a 200W power supply and when I added the Pinnacle Deluxe card all it did was crash. If I took the card out it stopped crashing. I have the exact same card installed in my new home build PC and it’s very stable. (as stable as any Windows system could be) My new PC has a 480W power supply. So random crashing could be an inadequate power supply but it also could be a bad device driver. It’s hard to say.

~jr

PS looks low.
They've beat this topic to death at
http://www.ocforums.com/showthread.php?t=252752&page=1&pp=30
And a quick PS calculator here: http://www.jscustompcs.com/power_supply/

As to the advice from an HP tech - weren't they the ones who built your PC to begin with?

If the crash was caused by something intermittent, it could be tough to track down. If you think it could be the power supply, then simply buy another unit and swap it. Generic power supplies are maybe $30. It might be that your HP has a special power supply, however (one strong reason for going the homebuilt route next time).

Some folks love BIG power supplies. I have found that a plain ol' 350w supply can handle my somewhat elaborate homebuilt PC (with 6 drives inside the case) just fine.

The other obvious suspect is memory. Here, too, simply get a replacement stick, or if you have multiple sticks in the PC then remove one for a time and check stability afterwards (xp runs fine on 256MB; it just won't be a fast at some tasks).

I've had several problems with RAM over the past 6 years, but never with any power supply. You can check for power adequacy by simply downloading the free Motherboard Monitor and installing it. It shows your various system voltages and an inadequate supply would show up as a sagging voltage. Can't help with intermittents, however.

In my own experience, here are the problems I've had with my Compaq and my own homebuilt PC's since 1998:

(1) Bad ram: twice (admittedly they were generic ram sticks)

(2) bad CPU: never

(3) bad power supply: never (though I replaced the meager 100w Compaq supply)

(4) bad drive: never

(5) bad hard disk power cable: twice

(6) bad hard disk data cable: once

Thanks for all the responses. I should have mentioned that I added the second hard drive after I bought the computer. But nothing else. I was told by the HP guy that 200 W was on the low end even before I added the second drive. I bought the computer through Best Buy, so I'm sure who is "responsible" for the problem.

Not much humidity here (I'm in the Sacramento, CA area -- I think there is about 20-30% humidity here). However, the room my computer is in can does get warm (80s).

Thanks for the calculator "mstrg"! A quick estimate shows that I should have at least 350 W. I'll try a larger power source and see if that helps.