Originally Posted by fitbrit
I'd stay away from the Pentium D. Too hot, too slow, too power hungry and probably too loud when cooling under load. Try to get a core2duo at least.
Have to disagree. I have a 6 year old Optiplex GX620 SFF Pent D that I "repurposed" as a secondary htpc, added a fanless Radeon 5450 for $30, installed W7 Home Prem, and it works great playing DVDs and streaming Amazon Video, ESPN3, etc.
And it's very quiet in its stock configuration.
To cenvalycali, make sure those models have a PCE-e x16 slot so you can upgrade the video card. Some models from that era do, some still have AGP. You can get a 5450 for as little as $15 these days.
There were a ton of those SFF GX620s used by businesses, and a ton that are still in circulation by the way. It was a really popular unit. I'm not familiar with the 745.
Plainly a C2D is better and lower power, and I wouldn't spend much on a D, but it will work. I wouldn't spend much on a C2D system either. You can build a current generation system for under $400, so these old systems are worth saving, but only if you don't have to invest much of anything in them. Mine cost me $30 and W7 license I had sitting around unused to keep using a system that otherwise would have been scrapped. But mine already had 3gb of ram and a 500gb hard drive. If you have to start buying ram or drives or the like, it's not worth it.
Particularly if you want to use it primarily for internet streaming, it will work fine. It's a lot faster than an Atom nettop. The SFF cases are pretty decent. Whether it's cost effective to buy one is a separate question.
It's not my main htpc and for what I use mine for, it's fine. I actually bought an SSD to stick in it to give it more life (besides, I can always re-use the SSD when I finally decide to build something new).
BTW, to cenvalycali, 2GB of ram should be sufficient, and an 80gb hard drive is enough if you're not going to ripping, recording or storing video on it. Just don't start sinking money into a 6 year old box. It will add up fast and quickly be a bad investment.