comparing this two cards for the price and performance, the price difference is about 25$ and for the performance in many reviews and benchmarks i've noticed 8fps avg between this two cards
so i think with little oc to the 6850 this difference can be decresed, anyway i want to ask is it worth to get the 6870 over the 6850?
you will see a reasonable boost in fps from 5770 to 6850, although not a huge difference. You should also consider a 5850 if you can still find any in stock. a gtx560 would be another option.you can OC the 6850 to near 6870 levels, but your really pushing the card, and would need to get a card with a good cooler which may cost you more and you will be coming close to 6870 prices. If you have the money, just spend the extra on the 6870. If you dont mind messing around with crossfire, just add another 5770 you will get equal to and in some cases, better performance than a 6870. It will also cost you a lot less. Also make sure your PSU is up to powering the setup you chose.
I got a couple of 6870s and I know just how much of a pain in the A@@ running crossfire can be and gave up and got a 6970 instead. While you consider overclocking a 6850 if you buy a 6870 with good cooling they overclock quite well which would move you closer to a 6950 preformance that you may not be able to reach with the cheaper card. Do you want to get the most useable time with your video card? Then I'd go with the faster one. For that extra 25 you may get a .5 or longer year span out of it depending on what you use it for.
I play games a lot and use a large HD TV and running the native 1080 setting I found I needed all the performance I could get out of the 6870 for some games. The memory was a slight issue as well with 1GB.
So I tried crossfire and while it worked with some it didn't with other and it was a hard fit to the case but it just was a royal pain so I ended spending the extra for the 6970 and it was a world higher than the 68 series even overclocked.
But I really could get fair performance with the 6870 and you should worry about the 25 extra as far as I can think. It will just give you a bit more leg room or longer use time.
Though with newest games they can really put a lot of strain on even the best video cards if you max them out. Keep this in mind. And if you get a custom cooling card watch out when their fans are running, I had a SATA come loose and somehow it the fan and broke 2 fins off. Those long fan blades are very easy to break so it's back to ASUS rma to replace a stupid fan that they wouldn't send me or sell me one so I paid in shipping 4 times the cost of the fan. Couldn't find a replacement fan for that card anywhere if I wanted the 4 wire control of the fan.
Oh well, I would recomend the 6900 series cards if you could afford it, I really would but only if your into games. The performance between them is worth it but a hard pill to swallow I know. I know I'll get more years use out of the 6900 series over the 6800 series to make up for the higher cost.
Got a card with a HUGE heatsink and fans that keep it cool with a stock 40mhz increase over the reference cards. It's very fast. I think it was a power color card that has been working great with 2 huge quite fans that keep it very cool with hard game use. Free game if you can really call them free came with it so all in all I thought it was worth the large price increase but if you can't afford it go with the 6870s with good cooling and if you need to you will have a lot of room to overclock it out of the 6850's range.