Double post.
"any cpu that fits this board will bottleneck the performance of your hd5450."
Not true at all. core 2 Extreme's/ Core 2 Quads and Core 2 Duo's don't bottleneck a card like that, it is a very old and slow card.
That board has this - PCI Express* x16 connector
Yes it most certainly will. PCI-E is also backwards compatible, so don't worry if the generation required is different from the motherboards.
Power supply, even though not specified about make/model will also suffice that card no problem.