The other input on my TV is HDMI and the picture is fine but with the Mac Mini outputting 1080p I see what for the lack of a better term I'm calling "sparkle" in all dark fields like backgrounds...probably the 50' DVI cable? It'd be a bummer to replace as my AV guy just ran it outside the house.

I'm surprised it even works. Awhile back in this forum another member reported failures at 25'. I'm never one to recommend high quality, high priced cables, but the longer the cable run the more critical cable quality can impact the signal. Are you sure it's not the anti glare coating on the LCD causing the sparkles? Have you tried lower resolutions to determine if the problem is resolution dependent? Do you have any other hdmi/dvi devices that you can also try to see if the problem persists?

I'm using this (http://www.monoprice.com/products/product.asp?c_id=102&cp_id=10209&cs_id=1020901&p_id=2185&seq=1&format=2&style=) cable.

I guess I will just connect my Mini via DVI -> HDMI to my receiver and just use the 50' HDMI cable running between my AVR and LCD TV to carry signal.

I had the same problem with a 50' cable and a Mini, it was the cable. Some of the cheaper cables are to thin and create those sparkles. I got a better quality cable (thicker) and no more problems.

I had a 50' DVI cable from my mini as well. In general, buy the cheapest cable. But if you are doing a long run a better cable makes the difference. I bought mine from RAM electronics, I think.

Prior to buying it I had read that cheaper 50' DVI cables can produce sparkles. I never had an issue with my cable (but I did spend about $100 for it).

I believe 50' is beyond the spec for both DVI and HDMI, but with high quality cables it works.

The drivers in DVI aren't specified as stringently as the HDMI drivers. Thus, you may get better results switching through a HDMI device, such as an AVR. I run my DVI out to HDMI in on my AVR, and then a long haul to my LCD HDTV, and it works pretty well.