The HD 6570 with DDR5 VRAM is overall faster than the HD 5670 with DDR5 VRAM.
Using DDR3 VRAM will probably drop the performance by about 5% - 10% which means that the HD 5670 will likely be overall the better performer by a small margin.
so really only a very minimal difference in performance
Hopefully they will offer the HD 7670 in a low profile
that series of cards HD X670 especially low profile must be a good seller
due to OEM towers in need of upgrades
Granted they are not very good for DX11 titles
but as far as DX9/10 they do okay
I was disappointed that the HD 6670 wasnt available in low profile
when I was shopping for cards in April
They reviewed a low pro HD 6670
but I never saw any for sale