HD4850 Drivers - Which to use?

First post, yay.. Anyways, lately my computers been acting up a bit. Monitor randomly turning off or freezing, figured I'd try updating my video card's drivers. So I did and I'm still experiencing random freezes at times. Weird thing was when I went to update my drivers, the 4850 wasn't an option. There was 4800 and 4890 in the list. Which of these should I use? Previously I was running the ASUS drivers that came with my card and it showed up as a 4850. I went ahead and installed the 4800 drivers assuming it meant the entire series and it's showing as a 4800, then later I noticed the 4890 was in the list, but not the 4850. Are they not released or something?

I remember a few years back a lot of people were using the Omega drivers instead, are they still up to date and performing well? Or is there a new third-party alternative that people prefer using nowadays?

Also, I'm running XP SP3 Pro, 32-bit.

Thanks ahead for any help\suggestions

That's what I'm using now, just wasn't sure which I should be using if they're fine. Lists 4800 and 4890, but not the 4850 which is what I have. Assuming the 4800, and hopefully it covers the 4800 series, just something about the 4890 was different and required it's own?