Xeon in my Dell Optiplex 360 worked. LGA 775 is the best socket ever : r/pcmasterrace
LGA 775 cpu list – all processors Intel:Xeon, Core 2 Quad, Core 2 Duo, Pentium, Celeron – LGA775 (771) socket (specifications) – CPU-LIST.COM
Intel Xeon E5450 (3.0GHz/12M/1333) Processor Close to LGA775 Core 2 Quad Q9650 CPU, Works on LGA 775 Mainboard No Need Adapter - China E5450 and Q9650 price
Intel Socket 775 Xeon X5460 X5460 Quad-core 3.16ghz 12mb 1333mhz Works On Lga 775 Mainboard - Cpus - AliExpress