I was just going through some All-in-one desktop PCs (Dell Studio One, HP Touch Smart, Lenovo Idea center, etc...) and their specs really look good (4GB RAM, 2.x GHz Core 2 duo, etc...)
Do you have any idea about the disadvantages of such PCs as a developer machine. I mostly do Java (Eclipse + MySQL + Tomcat / JBoss) or .NET (Visual Studio + MsSQL) development.
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One common question I could see is harddrive size and that's around 320 GB 7200 RPM.