This has been a consistent dilemma for me over the past few months, namely I have a lot of game consoles (N64, PS2, DreamCast, GameCube, Xbox 360, PS3) and a monitor to plug them into BUT nothing to upscale the output which looks really really ugly since the monitor I have does not upscale at all. But here's the kicker, it has to upscale HDMI sources in addition to component, S-video, and RCA sources since the PS3 has the worst output method known to man, namely it outputs at whatever the game specifies and does not upscale lower than 1080p sources to 1080p (e.x. Hotshots Golf outputs at 720p, and the PS3 outputs it at 720p instead of upscaling that to 1080p thus making everything look awful). Basically I need an all in one 1080p video upscaling box. Don't care too much about audio, it needs to be present and capable of outputting 5.1 but other than that I really don't care about the audio aspect of things.
Here's the part that is usually the deal breaker, I can't spend much over $1000 (and would prefer to spend much less) on it. Usually I can find receivers that will do part the stuff I want for that price, but not all. As of right now I'm stumped and strongly considering just buying a TV that will upscale for me, but I don't really have room for it even if I wanted to (most respectable 1080p TVs are about 37 inches, this monitor is 27 inches and that is straining my space constraints).
Given that Black Friday is soon, pointing me in the right direction even if the price is strictly speaking out of my range is fine.
Try googling for a video scaler that has sufficient inputs. There are some for about $500 that may do the trick. Check out the DVDO Edge. Audio is a separate issue but what you already have will continue to work