Replacement Video Card

Question

I had an XFX GeForce 9800GT 512MB PV-T98G-YDLH, but it started to have some serious issues (artifacts + BSoD) and I sent it back to XFX. They issued a replacement card of "equal-or-greater" value/performance, but I feel like the card I got may be of neither equal nor greater value: XFX Radeon HD 5670 512MB HD-567x-YNF3.

I can't find any reviews where I can easily compare the two cards head to head, but looking at their specs it seems that the HD 5670 might be a little better when it comes to numbers. The only thing that concerns me is that the memory bus on the 9800GT is 256 while the HD 5670 is only 128 bit:

GeForce 9800GT

Bus Type:   PCI-E 2.0
GPU Clock:  600 Mhz
Memory Bus:     256
Memory Type:    DDR3
Memory Size:    512 MB
Memory Speed:   1800 Mhz
Thermal Solution:   FANSINK
Minimum Power Supply Requirement:   350 Watt
Outputs:    HDTV, , Dual-Link DVI

Radeon HD 5670

Bus Type:   PCI-E 2.1
GPU Clock:  775 Mhz
Memory Bus:     128 
Memory Type:    DDR5
Memory Size:    512 MB
Memory Speed:   4000 Mhz
Thermal Solution:   FANSINK
Minimum Power Supply Requirement:   400 Watt
Outputs:    HDMI, Dual-Link DVI, Display Port

I'm not very up to date on the new video cards, so given the above specs:

1. The Radeon seems superior in all other aspects, but how much impact does the 128-bit memory bus have on performance?

2. Does anybody have any links for real-world performance of the two cards that can tell me if the HD 5670 is in fact equal-or-greater value/performance?

3. Should I ask XFX to give me a different card, or is this a "fair trade?"

Answer 1

The 5670 is more or less equivalent to 9800GT in terms of performance. Consumes lesser power than 9800 GT. Seems like a fair trade to me.

but how much impact does the 128-bit memory bus have on performance?

Not much. The GDDR5 makes up for it.

Here's a decent comparison of the 2