Re: looking for video card with best HDMI picture
There are some differences in the quality of the deinteracing they are capable of. Generally it is recomended that you stick to the 5570 or 5670 if you want the most capable 1080i deinterlacing performance. After the 5670, there is no difference in quality. going 5770 or 5870 or 5970 will gain you nothing. If you watch a lot of 1080i content, like from a HD-PVR, then it would be worth it to upgrade to one of those 55XX cards instead of the 5450 which is a really slow card and only handles bob and weave deinterlacing.
If you just watch blu-rays and other progressive content like ripped movies from torrents, hulu, etc, then you could go with the low end card. They will all accelerate blu-rays the same.
I would go for a fanless 5550 with DDR3 memory personally.
But, the only real difference between the 4XXX cards and the 5XXX cards is bitstream audio support. You already have a 4XXX card which is a good card for playing blu-ray. There is no difference in picture quality of a 1080p video between any 4XXX card and any 5XXX card. I’d stick with your current card and check out why the picture looks bad.
Try text on the screen from a website. Does it look sharp and readable? If it doesn’t then fix that before you start to quibble about little things most people won’t notice like Vector Adaptive deinterlacing on a 5570 video card vs bob and weave on a 5450.