1280x1024 JPG vs 1600x1200 PNG on a 1280x1024 desktop?

Hmmm… I’m guessing that this is the right place. No ‘graphics’ section.

I’ve got a load of rather gorgeous wallpapers in 1280x1024 & 1600x1200 JPG format but also 1600x1200 PNG format.

Now, I don’t know what’s best to use as desktop? Between 1280x1024 and 1600x1200 on my monitor which is a 1280x1024 native display, the 1280 is a no brainer as far as JPEG goes… but what about the 1600x1200 PNGs?

I believe that PNG allows for some rather impressive effects over JPEG so would it be best to use the 1600 PNG versions or 1280 JPG versions of piccies on my desktop?

Cheers folks!

PNG is lossless, but if the JPEG is high quality it should not be a loss for usual bg usage.
I doubt that you need Alpha transparency or MNG animation as wallpaper??