Solandri said:
The Dell 700m is a very old computer. I'm actually surprised you were able to even get Win 7 installed on it.
Newer video Codecs require a lot of processing power to decode. To prevent them from sucking up too much CPU, Intel, AMD, and nVidia have added circuitry to their GPUs (integraded or discrete) specially designed to help decode these codecs (sometimes referred to as video hardware acceleration).
The video card on an older computer like the 700m was released before some of these newer codecs were even invented. It doesn't have this extra circuitry to decode the newest codecs. Consequently, the computer has to decode it in software using only the CPU. What's likely happening is the video players are detecting the CPU isn't fast enough to decode the video in real-time at your resolution and bit depth (number of colors). So rather than make the video stutter (wait to decode, display, wait to decode, display, etc - what you experienced in Windows Media Player), they are downgrading the image quality (mainly the bit depth) to something your CPU can handle in real time.
There's nothing you can do about it short of getting a newer computer. If you're lucky, the real problem is that the player is not properly detecting your video card's capabilities. If you dig through the advanced options in your player, you
might find obscure setting(s) which will work for the video card in your computer if you manually set them to the right settings. I've actually done this to get HD video working (barely - 720p ok, 1080p no way) on a Core Duo-era laptop. But yours is even older. And it's almost entirely a guessing game as you enable and disable different settings.
I suppose another option is to re-encode all your videos to an older or less processing-intensive codec (Handbrake has such an option). But that takes a lot of time especially on an older computer, and will make the movie file larger in size. If you don't want to upgrade your laptop but have another newer desktop computer on the same network, you can try installing a media server like Plex which can transcode the video in real time into something your older laptop can handle. Then use the desktop to stream the video to the laptop.
Its an Old laptop no doubt, but believe me when I say that I have watched 720p on a 600m which is even older and has a much slow processor...I did some digging and found out that I had an ATI driver installed on that 600m machine...Also many of my friends have Asus eee-pc and there machine works fine even with 1080 quality videos..and when I tried playing a 720p on my eee-pc the same problem occurred as it did on 700m...If anyone knows of a good video driver for either eee-pc or 700m please mention.