ATI Radeon HD3870 - 512 MB DDR4

I want an opinion on this SAPPHIRE graphics card - ATI Radeon HD3870 - 512 MB DDR4 - PCI Express if it is, whether it's worth it or not for games my motherboard a MSI - KA780G - AMD 780G - SB700 proc 6400 + at 3.20GHz 2x1go pc26400 g.skill pros and under vista 32bit

Thanks you for your advice

takes a 4830

the hd4830 DDR3 is less efficient than the hd3870 ddr4
GPU: ATI Radeon HD 4830
Clock Speed: 575 MHz
Video RAM installed: 512 MB
Technology: GDDR3 SDRAM 256-bit
Speed basis of memory: 1.8 GHz
Features: Dual Slot Fan Cooler, Avivo HD Technology, ATI CrossFireX Technology
and hd3870
GPU: ATI Radeon HD 3870
Speed of the central clock: 775 MHz
RAMDAC Clock: 400 MHz
Video RAM installed: 512 MB
Technology: GDDR4 SDRAM 256-bit
Speed basis of memory: 2.25 GHz
Features: Avivo HD Technology, Integrated HD audio controller, ATI CrossFireX Technology