New PSU for a Deminsion 4600?

Understand.  It should be fine, but you're right; "you get what you pay for".  As a general rule, any power supply under $50 before a rebate if offered is considered cheap and not recommended.  At least you have a one year warranty.  Don't forget that the XFX card does require an additional power connection from your PSU by a 4-pin molex cable which you should have unless you happen to be running two hard drives and two optical drives and have used them all.  The new power supply shows to have 4 like your old one.  If for some reason this power supply does not work, I would just try running it off the old one as it really does not need that much power.  The total system draw with an AGP HD 4650 is shown to be only around 170 watts. 

Thanks for the info. I was going to see if my 250w would work  ( i used a Power supply calculator and it said 213-265 ) but it is very old ( bought in 2004 ) so i hear that it would reduce it anywhere from 10 to 35%. I dont want to ruine this PS as i will most likely set it aside for that just in case moment after i clean it up really good . I live in southern cali and also would love two add two 80mm fans i have to it to help with the heat. This is a reason i figured i might as well up the power a little. My old GFX card was at a constaint 57-60C with NO LOAD and i believe that has to do with the fact it is always like 80 to 90F in my room lol.

The PSU only costed me $28.18 and all i need is for this comp to last another year or so. Once i am able to return to work this unit will be put in a closet for back-up use as i bring in a new machine. I have to admit, this Dell Deminsions Has out lived my expectations and has been a trooper. Perfect work horse and the only things that has ever went out on it was my GFX cards, 6200 popped and a 7600GS EXPLODED, sounded like a m-80 went off in my case. When the 7600 popped i thought that was it but the card and machine just kept working. One of the cap. blew so i guess it just didnt want to let go so when it did pop it was REALLY loud or it was just really quiet here in the house and seemed loud

I'm not sure where you would add those fans except perhaps upfront on the hard drive cages.  If you plug them directly into the power supply with a 4x Molex, they will run at full speed and may be irritating.  I tried this on another Dell model to bring air in from the front, but it was so loud I immediately took it back out.  This is why the 120mm or larger fans are nice because they can run at full speed and move more air and not be noisy compared to 80mm fans.  I had a 7600GS in my 4600 at one time, but the motherboard went out before anything else so I parted out everything and sold it.  Older cards tend to run hotter than the newer ones depending on what you have.   I had a 9600GT that idled at those same temperatures at 57C and a newer GTS 250 idles around 37C - 40C in the same case.  Some ATI cards have been know to run hot.  You still may be looking at idle temps in the 50C range and load temps in the upper 70C range with the HD 4650.   

You're welcome.  It sounds like things have worked out well for you.  I actually have another Dell 4600 from 2004 in the house that someone else uses that I had bought used last year.  I will have to remember the parts you bought if I need to upgrade it down the road.  It is currently running with a BFG 6200OC and the stock power supply.  Hopefully, everything stays cool, quiet and keeps on ticking for you.