I'm wondering which would be better considering the price. Someone is selling a 2900 XT locally for $250 and i have checked the canadian prices, and $300 after taxes and shipping is the best i can do for the HD 3870. So my question is, which would you get?

They perform about the same in most situations, with the 3870 usually edging ahead a little.
The 3870 has a much lower power consumption, but that 2900XT is cheaper.

You should probably go for the 2900 is your're not bothered about its high power usage.

I don't see any 3dmark records being broken by the 3870. But I do see some with the 2900.

I guess another question would be. Can your PSU handle the 2900? If not then the 3870 is the way to go.

If anything, with its 512 bit bus, the 2900xt is the 'full red-blooded' radeon. If power consumption isnt an issue, and you have at least 2x6 pin power connectors, then its a good buy. Performance wise, you can look at it as the older, hotter hungrier 3870. It should be able to run crysis with dx10 hack on XP with 25-30fps @1152x864 and below. It will run every dx9 game very well.

Dont forget the UVD and...well...ok, DX10.1. Also its quieter, and new enuff to maybe benefit from new driver releases somewhat. Or wait a week or two and get it cheaper as more hit retail

Why not posting some reviews:

http://www.hothardware.com/Article [...] 5nm_RV670/

The new Radeon HD 3870 performed much like a Radeon HD 2900 XT. The two cards generally traded victories over each other depending on the game and resolution being tested. Due to its smaller frame buffer and lower clock speeds, the Radeon HD 3850's performance was somewhat lower, but in comparison to what are expected to be similarly priced mid-range cards like the Radeon 2600 XT and GeForce 8600 GTS, the Radeon HD 3850’s performance is quite strong. NVIDIA’s GeForce 8800 GTS, GT, and of course GTX usually performed better than the new Radeons, however.

http://www.techreport.com/articles.x/13603
http://www.anandtech.com/video/showdoc.aspx?i=3151

The 3870 & 3850 reviews dont use the same drivers for all the ati cards. I reckon the first reviews/benchmraks that include the 2900xt & 3870 using the same drivers will show they are almost identical in performance.

...or just wait for availability of the 3870 & 3850 to improve and prices to drop.

I for one think that the 2900pro/XTs 512bit bus is not full utilized. I also believe that AMDs pushing ATI to throw out something fast has caused them the time to get it working like it should.

ALso if you could have gotten the 2900Pro I would suggest it. Especially the 1GB version as it has GDDR4 and can OC pretty good. I personally think everyone should wait till early 08 cuz I am sure NVidia and ATI will release another GPU that is better than anything out now.

I think the HD3870 would be better. Due to the power efficency of the HD38XX cards I think the HD3870 will likely sell better and as a result there will probably be more focus on ATI's part for creating better drivers for it.

If you are going to get a 2900XT you better have one helluva power supply in your rig.

Personally I would suggest a 3850 instead. They are plentiful in supply. I think it is going to be ATI's main cash cow going in to 2008. Plus the 512MB verison is going to be available in less than 2 weeks and it is only going to cost a hair more. http://www.fudzilla.com/index.php? [...] 4&Itemid=1

Face it. Current high end cards can not play Crisis at 60 fraps right now. To get that type of performance off of a single card you are going to have to wait until 2008 when both Nvidia and ATI offer stronger cards.

A 3850 should be able to max out any game if you have a 22" monitor or less.

If you are going to sink a lot of money in to a card do it in 2008.

The world has not made a full transition to DX10 yet and the current cards don't run DX10 games at the levels their publishers intended them to.

Save yourself money and just get a HD3850 for now.

The R700 is what you want to get in 2008.

http://www.fudzilla.com/index.php? [...] &Itemid=34

Buy a 3870, just shop around, Directon has some in stock for less then Newegg. I did. GDDR4 512 Direct X 10.1 Shader 4.1. It is the latest set-up available.

"If you are going to get a 2900XT you better have one helluva power supply in your rig."

Its power hungry but not that power hungry. A 600w brand name supply should do fine. I even heard of someone having 8800gt's sli'd with a quad core intel all on a 550w supply. He said it was stable so apparently no problems with power fading off under heavy load there.

You would do well to wait for availability of 512mb 3850s and 3870s at a reasonable price. But if you want to go for it, the 2900xt has straight performance as one big plus. The 512 bit bus might not be being fully utilised, but even if its say just 75% used, then thats an advantage the 3870 doesnt have, and would explain why it needs much faster ram than the 2900, to make up for lost bandwidth, and why the 2900xt beats the 3870 in some games.

I am wondering how the 2900XT with 1gb gddr4 is performing on latest drivers. I also agree that the 512bit bus probably wasn't being fully utilized on the 512mb version. All you have to do is look at the 8800gts cards, and the performance difference between the 320mb and 640mb versions, on the 320bit bus that those cards use.

I also wonder how much of a difference there is between the 3850 512mb version and the 256mb version. I'm anticipating a possible 756mb version of the 3870, would like to see what the card can do with memory at 3x the size of the memory bus.

It's my opinion, that you never fully utilize bus width on memory until your memory amounts is 2 to 3 times the size of the bus width in MB. And from looking at how certain cards perform, it seems to be a realistic opinion.

or you can do what i did, buy a 2600XT to go with my X38 mobo very very cheap and wait until february 2008 and drop $700 on the NVIDIA 9SERIES D9E 8800GTX KILLER

no one knows exactly when the 9xxx series will come out, they are all rumors