How important is VRAM?

[- Ice]

Hello guys! I'm a first-time PC builder, and I want to do this to take better control of my gaming experience and not letting any sweet-talking sales rep make me regret my purchase decisions 2 months down the road.

I've been reading up as much as I can on video cards and have decided on a nice USD300 budget. With that, I have 3 cards lined up:
BFG Technologies GeForce GTX 280 1GB, 602 Core, 2.214 GHz GDDR3 Memory Clock = USD285
Sapphire Radeon HD 4850 X2 2GB, 650 Core, 1986 MHz GDDR3 Memory Clock = USD285
Sapphire Radeon HD 4870 512MB, 750 Core, 1.8 GHz GDDR5 Memory Clock = USD 280

Now I'm wondering if the VRAM on a card has any significant impact on it's performance? I know higher Core and Memory clock speeds means faster performance, but will the VRAM affect the overall result in any way?

More specifically, will the HD 4870 outdo the GTX 280 due to higher core speeds and a GDDR5 memory? Or will the HD 4850 X2 pwn them all due to the X2 config and 2 GB VRAM?

Thanks in advance for your opinions. I know I can just get a GTX 295 or a 4870 X2 and get it over with, but I'm on a budget and would like to keep my options open for future (a year or so from now) upgrades.

 

[Annisman]

Out of those 3 cards the best performing in order will be the 4850X2, GTX280, then the 4870512.

Now, the 4870 is going to be the cheapest solution, they can be had for around 150 USD $ after 20$ mir. http://www.newegg.com/Product/Product.aspx?Item=N82E16814131140

The 4850X2 2GB version is 340$ http://www.newegg.com/Product/Product.aspx?Item=N82E16814102809

and the cheapest GTX280 is around 290$ http://www.newegg.com/Product/Product.aspx?Item=N82E16814143141


With all the prices and performance of the 3 cards that you are looking at, your best price/perfomance choice would be the 4870 512. With that being said, to answer your main questions, Vram is much more important at high resolutions, in games with lots of textures.

If you plan on running your games maxxed out at 1680X1050 or lower, I would think that 512 of V ram is acceptable, at 1920X1200 you may want to look at upping it to 1GB of V ram, and at 2560X1600 1GB is vital, even looking at some newly released 2GB versions of the GTX 280, and 4870 Toxic would be recommended.

I hope I answered your question.



Also, if you want to stay cheapish and not worry about V ram limitations, this 4870 1GB can be had for 190$ http://www.newegg.com/Product/Product.aspx?Item=N82E16814102801
I own this particular card, and the aftermarket cooler on it is both quiet and very efficent at disappating heat.

 

[Euphoria_MK]

I agree with annisman, but I would rather go with this card if you are to pick the HD4870 !GB
http://www.newegg.com/Product/Product.aspx?Item=N82E16814161269

It's $189 or $169 after rebate, and it performs great. With stock cooling you can easily OC to 790/1000

Cheers

 

[coozie7]

Generally 512Mb is enough for 16x12 or lower, over that resoloution and the extra memory becomes more importaint, not so much for FPS but in the elimination of `glitches` caused by the system having to swap data in and out of VRAM from hard drive, which will, obviously happen less with more VRAM.
Your upgratde options will be affected by your current motherboard. Is it single card, SLI or CF capable?
Me, I hate multi-GPU setups anyway so I`d go for either the 1Gb HD4870 or the Cinderella card here which is the GTX260 216 (both can be overclocked to get close to the GTX280s speed and are much cheaper).