Use base model for primary key.

Cicm.Database/Models/ProcessorsByMachine.cs

@@ -32,13 +32,12 @@ using System.ComponentModel;
 
 namespace Cicm.Database.Models
 {
-    public class ProcessorsByMachine
+    public class ProcessorsByMachine : BaseModel<long>
     {
         public int ProcessorId { get; set; }
         public int MachineId   { get; set; }
         [DisplayName("Speed (MHz)")]
         public float? Speed { get; set; }
-        public long Id { get;      set; }
 
         public virtual Machine   Machine   { get; set; }
         public virtual Processor Processor { get; set; }