1gb 4870 or crossfire 4850's

Crossfire 4850's if you have the motherboard for it obviously.

Go for the two 4850s then. Also depends on your monitor size/resolution. That is really the most important.

The 4870 is awesome but the 4850 offers the best bang for the buck.

Since DDR5 is not mainstream memory yet you are going to be paying a premium for 4870 cards.

Two 4850s cost the same as a single 4870 and out performs it by a significant amount.

Just make sure you have a strong enough power supply and your case has good cooling.

Two 4850's do not cost the same as a single 4870.

http://www.newegg.com/Product/Prod [...] 6814102770 - cheapest 4850, x2 = $320

http://www.newegg.com/Product/Prod [...] 6814121276 - cheapest 4870 = $250

Then there are the "hidden" cost, of needing a Crossfire mobo ($120-$200, depending on if you want 8/8 on a P45 or 16/16 on a X38/48. Or $180 for a 790FX w/SB750 for 16/16, or a $110 790GX with 8/8), and a larger PSU than you would use for a single card solution. And the 4870 is priced well for what it offers, and you arent really paying a premium for GDDR5, considering its $50 cheaper than the GTX 260 216 that uses GDDR3 and performs about the same. GDDR5 is better, period.

Thx for the help guys.....Ill be using a 22 inch monitor which has a res of 1680x1050 i belive. Also to make it clear this is a 1GB version of the 4870. comparing the prices thier both about $300.

kk thank you very much for the help.

Dual 4850 will far outperform single 4870. They're not in the same league. The extra $70 is a lower % price increase for higher % performance increase.

As for ddr5 and ddr3, it's not nearly as important as most people make it out to be. To say that "ddr5 is faster than ddr3" is a gross oversimplification, and often wrong.

Use this formula for memory access bandwidth/capability:
(ddr# - 1) x single channel clock = effective clock
(Bus bandwidth / 8) x effective clock in ghz = overall capability

Let's do a bit of calculation:

4850 = 2 x 993mhz = 1986mhz -> 1.986ghz
4870 = 4 x 900mhz = 3600mhz -> 3.6ghz
gtx280 = 2 x 1107 = 2214mhz -> 2.214ghz

4850 = (256/8) x 1.986 = 62 gb/s
4870 = (256/8) x 3.600 = 115.2 gb/s
gtx280 = (512/8) x 2.214 = 141.7 gb/s

Imagine it as 2 rivers, one is narrower, but flows faster (ddr5, with 256bit bus), the other is wider, but slows slower (ddr3, with 512bit bus).

Of course, since 4850 also use 256bit bus, its memory is slower than 4870, unlike gtx280. But still, performance is determined mostly by the processor itself. Higher bandwidth, whether it's in the form of ddr5 or wider bus, is only a contributory factor. 4850's core is almost as strong as 4870, and benchmark performance reflects this, as 4870's performance edge isn't nearly as high as the 115.2/62 ratio would suggest.

Hope this sheds some light on ddr3-ddr5.