Is the ati radeon hd 4850 a good video card

It'll work great, though it depends on what your definition of "high end" is. It's an excellent midrange card, IMHO, although to get to truly high end, you'd need to go to something like a 4890, GTX 285, or one of the multi-GPU setups.

what about the hd4870 is that a better card

It would be helpful for you to give us your budget so we can better advise you.

the 4850 can ''play'' every game it just depends on what res, details ur playing it on. imo the 4850 is a great card for its price for gaming around 1650x1050 . not higher tho. if you plan to play on higher resolution go for 4890- or gtx275 or higher like the dual cards.

Both the 4850 and 4870 will go up to 2560x1600 (assuming the monitor supports it). However, the 4870 will work better at higher resolutions like 1920x1200 and up (especially the 1GB version).

The higher the res, the higher the demand on the gfx card, as it has to fill all those pixels at a decent rate to keep up, without showing lagging or worse, slide show effect.

sapphire is ATIs main brand, theyre good

If you stick with the reference design, it wont matter, other than customer service and warranties etc

Kind of late, but I have a Sapphire 4850.

-On Newegg it's been discontinued, anyone know why?

-Also after reformatting my computer, and installing the latest catalyst drivers for windows xp, the graphics resemble on-board graphics. Can anyone help with this?

* Also to mention, I don't have a true monitor. I'm using a 22" tv that supports 1080i and below. I've upgraded to a monitor just waiting on it now. *

Hardware:
e7300
asus p5q pro
4gb mushkin dual channel ram
500w antec neopower psu