For my 12-yr old son's Dell Inspiron 530 computer (3GB RAM) built in February 2009 with 19" monitor (1280 × 1024 resolution) and integrated graphics, I have considered buying and installing HD 6670 DDR3 ($65), 6670 GDDR5 ($89), or 7750 ($109). Prices I list are average, though the 7750 is consistently standard at $109 and is higher if getting the version without the fan.
Anyway, all three are low power cards and should be fine with my son's existing 300 W power supply. The power data I have seen is that while the 7750 idles with the least power of the three, it generally can use as much power with a load, though the data is inconsistent. Nevertheless, they all seem close in power demand, and all much less power demand than other cards except for maybe weaker cards like the 6450 or 6570?
The 7750 does seem take more room including two slots the best I can tell. In contrast, the 6670 is a single slot card, which I like that. Moreover, as for performance data, the 7750 is not anywhere close to twice as powerful as the 6670 GDDR5 but the 7750 is more powerful and newer technology, and only $20 more.
I would like the 7750. However, I can get the 6670 DDR3 for $40 if the $25 rebate goes through, and the 6670 DDR3 will likely serve its purpose well for the mild gaming my son will do on his computer, especially with his 19" monitor and modest resolution setting. I may get the 7750 for my computer which has a stronger processor and a bigger monitor.
Wow. That's a great comparison. Thanks. With the two links, I can see side-by-side performance for the main game he wants to play (Diablo 3) with the three cards I am considering:
7750 ($100 after rebate)
6670 GDDR5 ($70 after rebate)
6670 DDR3 ($55 after rebate).
The fps is almost double for the 7750 as compared to the 6670 DDR3.
I wonder (at his 1260x1024 resolution) if the Pentium E5300 2.6 dual-core processor (800 MHz, 2MB) will bottleneck the 7750 and thus bring the 7750 performance down more close to the 6670 DDR3 performance.