So something like the HP EliteDesk that @airdronian just used to replace his aging Mac mini running an Audirvana server then?For a cheap fanless modern server computer consider repurposing a newer thin client style of computer, especially if you are going to maintain your music files on an outboard hard drive. I have played around with several different ones and really like the Dell/Wyse units with Quad core processors. They work well with Linux. I like the 5020,7020 and 5060 models. They all can support 16 GB of Ram. I have been able to stuff laptop SSD units into the 5020 and the 7020 boxes. I haven't tried to put one in the 5060 yet. These computers and the similar products from HP can be easily found on eBay.