The million dollar question these days seems to be what video card people should buy to watch high-definition video on Windows Vista. If I had a dollar for every time I’ve answered this question… well you get the point. So I’m just going to post this info and start pointing people here.
Laptops don’t allow you to upgrade your video card, so there’s not much point talking about mobile parts unless you are looking to buy a new laptop. Laptop video cards are integrated with the mainboard, and how well it will perform is generally a factor with how it was implemented. For instance, an ATI x200 Mobility graphics adapter can do pretty well if it is paired with the right memory – and I don’t just mean the amount of memory, but the bandwidth as well. That card with a good chunk of dual-data channel memory can perform pretty good – pair that same card with single-channel memory and you may not have the best experience. For that reason, you can’t just make a blanket statement about the performance a particular mobile graphics chip – it’s all about the system it ships in. But back to the people who can upgrade their desktop graphics cards…
There are two big players in the discrete graphics market, and if you ask any of your friends what graphics card they’re using at your next LAN party (I’ve only been to one of these but the wife’s ridicule has lived with me ever since), and it will either be ATI or Nvidia. So, that being the case those are the two graphics manufacturers we’ll look at.
Nvidia and ATI took slightly different approaches with their hardware design – Nvidia has dedicated video processor chips on their cards, while ATI has dedicated logic units in their GPUs to handle video processing. Both of these are reasonable implementations, although in theory it seems that there may be some slight advantage in having a dedicated video process unit with Windows Vista. This would allow the GPU to spend more of its time crunching on the 3D-heavy DWM (painting the desktop) while concurrently processing the video stream. In reality, most of the current cards are beefy enough to handle small limitations.
If you go with Nvidia, then minimally I would recommend a 6600GT (note the GT on the end) card for HD content to be watchable. The amount of VRAM and the memory bandwidth are two key HW requirements for getting HD to play properly. The 6600GT has enough of both to work pretty well – I have a 6600GT w/ 128MB VRAM on my main desktop running multi-mon at pretty high res’s and it still works solidly for me on Vista. If you want to pay more money for a card in hopes it will last longer, then I’d recommend a 7600GT or greater.
If you go with ATI, then minimally I would recommend an x800 card for HD content to be watchable. I have an x800 XL card that’s been running Windows Vista x64 for the last year, and it has been working very well – and I keep the TV going through Media Center perpetually on this box. If you are willing to shell out more money and get one of ATI’s newer cards, then I’d recommend an x1600 or greater.