ati or Nvidia which one to buy?

There are a lot of cards from both nvidia and ati...both good and bad... i suggest you check this link first.

http://www.tomshardware.com/2008/03/05/the_best_gaming_...

Why don't you tell us a bit more.

What is your screen resolution?
What are your favorite games?
How long do you want to keep the card you're buying these days?
What kind of PSU and case do you have?

I agree, provide some more details.   Also, regarding the power supply question ^^^^^ take suggestions cautiously. People almost always tell you that you need more than you really do. Providing your power supply is of good quality, you can get away with a decent ammount. For example, with my qx6700 overclocked and 8800GTX overclocked, I pull only ~375 watts from the wall under load, and considering ~80% efficiency, the PC components are only using ~300 watts. So a good ~500 watt will suffice for pretty much anything less than any card without SLI/Crossfire. The keyword here is good quality. Good luck.

find cheapest of
Asus EN8800GT TOP
XFX GeForce 8800 GT Alpha Dog Edition 512
Zotac GeForce 8800 GT Amp! Edition
or
Gecube turbo / HIS iceq3 (oc) 3870

If you plan to do SLI or Crossfire with your system make sure your mobo has the right chipset. I've been using nvidia exclusively for some time now as the last ATI card I got had some compatibility issues with Linux, not sure if that's still an issue floating around since I've basically avoided ATI for the couple years, definitely look into that if you plan to use anything other than Windows.

Videocard: ati x850 xt
Processor: Amd athlon 4800+
Mainboard: Msi K9n Diomond
Memory: 2gb ddrII
Soundcard: Creative Fatalty
PSU: 500 watt cooler master i green pow
Budget 400$
I am not much interested in 1gb video ram but i just want which is good in long run.As now i got ati x850xt and i am not able to play above 2.0 pixel shader games like bioshock,dirt,lasvegas,strangelhold and many more.Though these days i play cod4.If i buy mid range now,i doubt i be able to play games in 2008but not sure about 2009.These are just my thoughts and i prefer to get wise advices from u guys

One of these 8800GTS 512MB cards would be just fine IMO. The first one is BFG for $225, the other eVGA $230.
http://www.newegg.com/Product/Product.aspx?Item=N82E16814143119
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130325

Maybe this one:
EVGA 768-P2-N831-AR GeForce 8800GTX 768MB, $290
http://www.newegg.com/Product/Product.aspx?Item=N82E16814130072

I'm not sure it's worth $60 more. That is, it will be better at 1920x1200, but about the same at lower resolutions. In fact the 8800GTS G92 may be faster because it overclocks better.

There both great GPU makers, its really up to what you want to do. If your really big on testing and need the top scores for now it's nVidia, but that could change in a couple of months.

For gaming both work excellent. I started with nVidia cards long ago but ran into one that had problems in a couple games so I switched to ATi way back when the first X800 cards came out. I've never had a problem with one of there cards. I have tried Crossfire and liked it as well and plan on going back to it as soon as the new 4000 series cards are released (will be using that tax rebate for them). For now I'm using a single X1900XTX and it does the job very well.

If your using the system to watch a lot of DVD movies ATi is better but nVidia is closing in.

yeah i watch lot of Divx movies too but what u mean that nvidia is closing in.U mean right now nvidia dont deliver good performance while watching movies?

  My 8400GS is quite capable of letting me watch a HD Avi, DVD movie and T.V, all at the same time!  

Yeah, really, is ATI really better for movies? As in what, better looking images? Post some screenshots or links please.

I got an 8800GTX and it's just fine for watching DVDs as far as I can tell. My only complaint is that I can't watch a movie on a monitor and play a DirectX game on the second monitor at the same time. Can ATI cards and drivers do that, by any chance?

One thing need to be considered again ,in this page they compared

http://techreport.com/articles.x/13967/11

ATI Radeon HD 3870 X2 and GeForce 8800 Ultra and if u froogle the prices u will notice GeForce 8800 Ultra is above 600$ while ATI Radeon HD 3870 X2 is under 450$ and even on above link they made ati the winner.

The reason i am asking cuz i wanted to buy nvidia but i think what i am saying is worth debating

I played Crysis with both 8800GT and the 3870...the images looked "lusher" when i used the 3870. I thought maybe i was having a sore eye when i used the 8800GT...so then a friend of mine did the same..with the same inference. But then that's about it.... don't know abt the DVD playback...

@OP: Well, you mentioned a $400 budget, and the 3870X2 is more like $450. If you really like it, go for it. It is great value for the money, and it will last longer than the 8800GTS 512MB.

There are two things you need to know about it though:
- some games don't support Crossfire properly, if at all, and in those games the 3870X2 will actually be weaker than the 8800GTS because only half of it will work.
- your current PSU is probably unable to support it. Even if it can, it's kind of close to the max and you're most likely going to be operating at 70% efficiency. It would be smart IMO to get something like a Corsair 550VX (www.buy.com has it cheapest) or a Silencer 610W or 620HX when you have more money. That would reduce heat and your electricity bills.

http://ati.amd.com/products/certified/powersupplies.html#pstop

Spend less money now and more later IMO.
HD3850 will be great for cod4 or 8800GS both are well under $200.

I saw an x3870x2 for $380 at Frys so it seems like ATI is lowering the price to prepare for the X48xxX2. You may want to wait a month or 2 if you can to either get a better deal on a 38xx card or be at the top of the food chain with a new card and by then you should have a little more $$$.

I have a HD2900xt running 64bit vista ultimate and have no problems playing full screen games on my main display and watching videos from divx, to blu-ray on the other use HDMI adaptor on my LCD with the meager speakars adequete enough for watching tv/videos, and have my surround sound speakers going through other sound card. Or vice versa, depsnding on what im playing.

As for video cards...i personally would go with a pair of 3870's in xfire for $360, They outperform the HD2900xt 512 card but consume a fraction of the power and at a fraction of the cost. Can play crysis at 1280x1024 at very high settings, everything maxed out and maintain a low of 30fps in highly complex scenes, Avg FPS is around 50 and i'm running a dua core toledo chip OCed to 3.6ghz and change, having 4 gigs of ram helps too.

Nvidia isn't worth the cost to me, and besides i like the idea of being able to put my HD2900, x1950xt cf ed, and a pair of 3870's in 4 way xfire when i upgrade my board. =D.

okay after lot of discussion i think i will buy ati
ATI Radeon™ HD 3870 X2 .And thank you all for good advices and support

Come april the 3870 is going to cost $160 each...SLI 3870 $320....$100 cheaper than the X2.....SLI 3870 and 3870x2 are the same...(someone correct me if i'm wrong and OP ignore this post)....

The 3870 is an ATI card, you can't do SLI with it.

The MSI K9N Diamond is an SLI board, no Crossfire, which means the OP can't use two HD 3870 cards on it unless they serve different monitors.

For that motherboard, I see two good solutions in the $400 range. One is a single 3870X2 as we discussed, and the other is with two 8800GT cards in SLI.

i meant CF...lol..sorry im a little sleepy  

And i quite agree with the 8800GTS SLI..

Hmmm... $450+$15 shipping buys two of those BFG 8800GTS G92 cards. OK, it may be $30 more if they only give one rebate per household, I don't know. That could be very nice.  

But we're blowing the OP's budget here, we're in the $600+ area (450+15+30, plus 120 for a new PSU).  

@mrfrantik: what's your screen resolution? Or, if it's easier, what's your screen size? A 24" or larger monitor can run 1920x1200 or more, and typically justifies going with an SLI setup. For smaller monitors (22" or less) it's less useful.

I still stand by the trusty n powerful 8800GT. SLI 8800GT performs fabulously! One can get an 8800GT for ~$200. Unbeatable deal.

Comment about video quality... I have an 8800GT which is a fantastic card but a second PC with an old ATi Radeon 9600XT. 720p movies especially look subtly but noticeably better with the old ATi. Not talking massive amounts here but ATi image quality is better.

Whats your problem with that I have no problems doing that with my 8800GTX's, play a movie on the projector with one port for the kids and play a video game on the main monitor on the other port myself, the only thing I find is that my brightness contrast and gamma settings from the game seem to hit the movie as well, and of course I have to mute the game sounds...

Just tested this again under vista 64 bit (previously did this under xp) and was able to play a dx10 game on one screen and starwars episode 2 on the projector from the same card no problem at all in fact the brightness gamma contrast issues didnt seem to be present!

The only viable ATI card right now in the market is the 3870X2.

9600GT dominates the $150 price range,8800GT has the $200 one,the G92 GTS has the $250 one and then you have the X2 which can be called the best $400 card although honestly you can get an 8800 GTX(which i would chose over 9800GTX) for much cheaper.

Suffice it to say that both the 3870X2 and 9800GX2 dominate their price range but their price performance is certainly not very good.