The E 2160 seems better but it surelly costs more.
4000+ and M2N MX: 2.3k+2.3k=4.6k
E2160+XFX 630i U: 2.6k+3.2k=5.8k
Gigabyte 780G and X2 4000+ : 4.6k+2.3k=6.9k
The 780G mobo has PCIE 2.0 and supports Phenoms with AM2+ socket and also supports DDR2 1066 modules in dual channel. Its backward compatible with older AM2 X2s. And it has the best IGP ever nd is DX 10.0 supported. Its IGP performs even better than 7300GS.
So the IGP of 630i[7150] or 690G[X1250] has no chance.
U can get the 780G mobo with a low end proccy like 4000+ and later get a better proccy, when phenoms price gets to bottom. Even now the phenom has hit 7k mark. And get some ATI's HD 3xxx card to get some added boost in 3D rendering performance.
even the 2.2k HD 3450 is neck to neck with 8500GT when used in 780G.