What resolution should I render animations? (Basic specs inside)

I have 4 cores, with 2.3 Ghz each.
I have 6 GBs of RAM, 1 taken by vista, another 1-2 taken by various programs/Virus protections. (So I always have 3 GBs for blender.)

I let a 4 second animation bake and render for about 8 hours today, and someone said they couldn’t tell the difference between the 720p and 480p version. (It took so long because the liquid had a resolution of 300)

So, this got me wondering. Is it even worth rendering animations in 720p? Or should I stick with lower resolutions?

Yes. There will always be idiots who “can’t tell the difference” between HD and SD. Usually, this is just because they are watching on a crappy display. Don’t render in SD unless some god-forsaken delivery specs asked you to.

With my computer (crappy and old), I generally go for a “High-SD” 960x540 resolution. But with your nice system specs, I would stick to 720p. If you"re going for a really high-quality render, 1080p is good, but in most cases you can"t tell the difference between HD resolutions.

It depends on your output. If your animation is going to end up on a standard DVD (which requires video encoded at 720x480 (NTSC) or 720x576 (PAL)) then you don’t have to render in HD. If your animation is going to vimeo or on bluray, then you’ll want to render HD. If you’re creating an animation for a 320x240 window on a website, you can render at 320x240.

The only thing to keep in mind is that you can scale things DOWN to your heart’s content, but scaling UP can cause problems real quick. so when in doubt, 720P.