Help me build a $500 budget PC?

ASRock A780LM AM2+/AM2 AMD RS780L $54.99
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

AMD Phenom II X4 940 Deneb 3.0GHz $174.99
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

HP Black 22X DVD+R 12X DVD-RAM SATA Retail $25.99
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Antec NSK 4480 II Black & Silver with Earthwatts 380W $89.99
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

mushkin 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 1066 $61.99
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Western Digital Caviar Black WD7501AALS 750GB $79.99
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

And that will give you a total of $487.94. The 1TB Black is only $20 more if you need the space and I guess you can drop down to more standard DDR2 RAM to save a couple of bucks. Since I was thinking budget build I picked a DDR2 motherboard, but then I realized you aren't going to need a separate dedicated video card  . I suppose you can go with an AM3 rig instead especially with the excellent GIGABYTE GA-MA770T-UD3P at only $79.99, but it does require a dedicated video card as it doesn't have onboard video  .

Oh yeah, didn't include the price of a monitor. If you need one I guess you'd have to lower the price of some of the other components to fit one in.

ok so we also need a monitor in a $500 budget .... thats tough but

AMD Athlon II X2 250 Regor 3.0GHz + ASUS M4A78-E AM2+/AM3 AMD 790GX $178
http://www.newegg.com/Product/ComboDealDetails.aspx?Ite...

Patriot Extreme Performance 2GB (2 x 1GB) 240-Pin DDR2 SDRAM DDR2 800 $30
http://www.newegg.com/Product/Product.aspx?Item=N82E168...
[ no point in 4 gig of RAM for xp and it wil be afster than vista with 4 gig anyway ]

Western Digital Caviar SE16 WD3200AAKS 320GB $50
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

COOLER MASTER RS-460-PSAR-J3 460W ATX12V V2.31 Power Supply +
COOLER MASTER Elite RC-332-KKN1-GP $65
http://www.newegg.com/Product/ComboDealDetails.aspx?Ite...

SAMSUNG Black 22X DVD+R 8X DVD+RW 16X DVD-ROM $26
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Acer X223Wbd Black 22" 5ms Widescreen LCD $160
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Total is $509

The cpu and mb are great quality, powerful and should last well
the 22inch lcd in that budget surprised even me but in productivity aps a bigger screen is worth it IMO
The cost cutting was with the case and power supply which are fairly basic but will work fine
There no graphics card included because the mb has the best onboard graphics available , and can even play games

The OP isn't a power user. So the $60 AMD 7850 chip will do. A better mobo should be used with at least 4 memory slots. Look at Gigabyte, MSI or Asus.

BTW: Best Buy sells pre-built Compaq with AMD X2, 3GB RAM, etc for $370 - ready to run. But its limited to 4GB (fine) and doesn't include DVI/HDMI output. But includes vista but includes coupon for Windows7.

What If I wanted to go Intel?, what would you recommend then?

Belardo, I want to build...not buy from Best Buy lol. Thanks for the advice tho  

I'm building this computer for my dad. For my own build, I have much greater needs.

Anyway, on a side note (I want to upgrade my own build), is the Q6600 still one of the best Quads you can buy in the $250 range? Actually I think it costs like $200, but say I had $300 to spend on a quad, and I still have a 775 mobo, what would you suggest?

The Q9550 for about $219 for the LGA775
http://www.newegg.com/Product/Product.aspx?Item=N82E168...

Very nice! I like this build, thanks