Radeon 4850 vs Radeon 4870

Hello, Soon I am going to be upgrading my video card (and psu) when my birthday comes around (about halfway through march). I am looking at 2 different video cards currently. The XFX Radeon 4850 and the XFX Radeon 4870 (both 512 mb). I am looking for a card that will last longer then one year at being able to max out a game (and be able to run games and hopefully run them at high settings for a couple years *crosses fingers lol*). I am into a lot of games (less lately due to college and work). But right now my gaming list is fallout 3 (waiting for a new video card to really play it) and spore (I also own a ps3 so games i play online like cod4 and killzone 2 I get for that). The price difference to me is quiet a bit but if it keeps me from having to re-upgrade for a year or 2 (maybe even 3 hopefully) then it would definitely be worth it. I have picked XFX as the brand because I have never had any problems with their products and they even include a double lifetime warranty (I really don't need the double but it is handy if I ever need it ^_^). The price difference is about 50 dollars (plus another 75-100 [max] for a new psu since I would need double pci-e connectors and I would be using the molex adapter for just one pci-e)

My current specs-

CPU- AMD Athlon 64 X2 5200+
Motherboard- Asus M3A78 PRO
Video- Radeon HD 3200 (onboard video)
Monitor- 19" HP
Ram- 2 gig PC5400 (667 mHz)
HDD- 200 gig (needs to be upgraded soon lol)
PSU- Sunbeam 500 watt

Also If you have any suggestions for a new psu I am happy to hear them (I am considering this one- Ultra 650 watt, I prefer ones with lifetime warranties and I really don't think I will need one with more then 650-750 watts [my motherboard does not support dual video cards and next time I upgrade the motherboard I will just get new psu by then])

Thank you for any help.

Edit- One other thing The 4870 is rlly the most I will pay for a video card, which is still a little too much to me and I am looking at ati for the fact that they seem to be out performing nvidia and that my motherboard alrdy is running ati) But if you have any nvidia recommendations then I would be happy to hear them.

well my 19" is a widescreen and has a max of 1440X900....and i do have crysis but dont even like the game lol...

but another thought would be, would it be better to get the 9800 gt? (after looking up the 9800's, the price is about the same,maybe even a little cheaper for the ati, so this would be a bad option lol

Again I want it to be able to run all my games (although there arent as many anymore lol) at max settings and be able to do this for atleast a year (I know no one can predict it, it is just a vest guess kinda of a thing, but thank you . *crosses 4870 off the list*

Also any ideas on the psu?

Is that the native resolution? I'm pretty sure the native resolution on most 19" is 1280 x 1024, thats the resolution you want to run.

I got this 4850 and I love it. factor overlclocked from 625 to 640 ( got mine at 690) Great cooling pipes and an exhaust slot. Never goes above 55c. $125

http://www.newegg.com/Product/Prod [...] 6814127401

Comes with a free game too!

Of the ones you listed, neither are overclocked. The memory frequency diff is just a typo.

Native resolution on a 19" widescreen is usually 1440x900.
I just got this HIS 4850 for my rig. The cooler is very quiet, effective, and exhausts the heat from my case: http://www.newegg.com/Product/Prod [...] 6814161244
HIS Hightech H485QT512P Radeon HD 4850 512MB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported IceQ4 Turbo Video Card - $155
There's a $10 MIR, and it now comes with a free game (I'm not sure mine did).
For the PSU, I would suggest an Antec Earthwatts 500. It is quiet, efficient, and capable of powering even more powerful GPUs.
http://www.newegg.com/Product/Prod [...] 6817371007
Antec earthwatts EA500 500W ATX12V v2.0 SLI Certified CrossFire Ready 80 PLUS Certified Active PFC Power Supply - $70.

zip-
My native is 1440X900, also I dont think it is a typo because its also like that on the xfx website :-\....Also call me nuts but I dont overclock any of my components lol