So, today was my high school graduation and naturally, I got a good deal of money. Enough for a new video card, in fact. I'd been waiting and researching like crazy, and I finally settled on the Radeon 9800 Pro. It's got what I need and it's in my price range, so i went for it. Problem is, according to my system manufacturer my PSU is 50 Watts shorts of the recommended specs I found on tigerdirect.com. I can't find anything on the ATI website about system requirements, but let's say it turns out it says I need a 300 Watt PSU. For whatever reason, Dell gave me a 250. My question is this, I can certainly afford to upgrade it, but I don't that I'll be able to get to a store and get one for a bit. If I install this video card on a system with a 250 Watt PSU, what'll happen? I keep my room cool, so it won't over heat. I don't tend to do A LOT of things at once, so my box rarely runs at full capacity (to be honest, lately I've just been playing a lot of Diablo II, an older game that runs well even on P3 machines) so I won't be requiring full capacity from my system. Is it safe to use the card or could I damage my system?

Also, could anyone recommend a specific store/model for a PSU? That'd be greatly appreciated. From browsing I see they're in the $20 to $40 range. Is that generally accurate? Or are those prices on the high or low end? Thanks!

Not sure if 250 will work or not, and as for Dell and upgrading your PSU, you might find it a lot more expensive then a regular PSU. The only thing you can do is try it, If you have 2 CD-Rom drives, unhook one until you get the new PSU. Be sure to turn off the on-board graphics in the BIOS setup screen.

One more thing, Get at least a 400 watt PSU. 300 is also weak.

Yeah, I decided to simply get a new PSU, 400Watt, along with the video card. Thing is, I don't know for sure if I'm getting the right kind. I assume I need a standard ATX power supply, I'm in the middle of a help chat with Dell as we speak, but they're most unhelpful.

I'm not 100% certain, but it's very possible that a Dell PSU is proprietary...meaning that you can ONLY use a Dell unit due to different plug/wire configuration. It also means that it will be more expensive...

If that's not the case, be sure to do your homework before you buy...the important thing is how the amps are distributed across the various rails (+3.3v, +5v, +12v). Go to the following site & read it over carefully:

http://www.firingsquad.com/guides/power_supply/default.asp

I don't know... you would probably need a standard... if you had an hp I would be almost positive that you would need a mini atx psu.. but I think your right... good luck... and don't pick the cheapest psu... but also don't get the most expensive... look at the + rails and make sure that the 12+ is at least 20a or higher...

Shuttle AN35N-Ultra
AMD 2000+ 1gb 2100ddr
Gainward Gforce 5600 128ddr
120GB of 7200 HD space
UV Clear Acrylic Blue case
POWMAX 400watt PSU
Leadtek Winfast Tv2000xp Deluxe Tv Tuner<b

Dell HAS used non standard power supplies in the past. I'm not sure if they still do. I would advise checking VERY CAREFULLY. You could completely fry your complete system with the wrong power supply.

I called Dell, they told me I could go to a store, buy an ATX PSU and it'd work. I'm reading the article posted above and I'm at the part where I calculate how much power I need on each rail...but how do I know what runs on each rail?

almost every component runs on the 12+ rail.. all of the 4 pin molex's are on it.. you don't really need to caculate.. it's just best and safest if you get one that has over 20 amps on it.. if you like I can suply a link that will help you better understand..

I think this is it http://www.firingsquad.com/guides/power_supply/default.asp

Shuttle AN35N-Ultra
AMD 2000+ 1gb 2100ddr
Gainward Gforce 5600 128ddr
120GB of 7200 HD space
UV Clear Acrylic Blue case
POWMAX 400watt PSU
Leadtek Winfast Tv2000xp Deluxe Tv Tuner<b

That's the same link I was referring to.

Did you read the entire article? There are charts with the approx amps required by each component & which rail it pulls that amperage from...

The +12v rail is critical...here's the link to the charts...rad the ENTIRE article...it's several pages long:

http://www.firingsquad.com/guides/power_supply/page2.asp

I might as well hit you with these sites while I'm here...especially this one:

http://www.sysopt.com/articles/PSU_Perspectives/index.html

This clip may not apply to your situation, but for anyone else following this thread, it could be helpful...it was taken from the above site:

"Dell owners beware! Prior to their conversion to standard ATX12v-compliant ATX power supplies for the P4, Dell used a variation of the ATX form factor with the power pins in a different orientation! Use of these older, nonstandard units on a standard ATX motherboard will at best refuse to work, at worst fry the board. Use of standard ATX power supplies in these older Dell computers will usually fry the power supply, or worse fry both the power supply and motherboard!"

http://www.jscustompcs.com/power_supply/

PC Power and Cooling has Power Supplies that work with a Dell. I bought one a long time ago for a 450MHz machine. Just tell them it is for a Dell and the model number.