That could uncover issues in both cooling and an old motherboard. For now I take it you did the BIOS update and a clean install of the OS and drivers.
If not, tell when you can get to that before we get into hardware areas.
So i bought a gtx 1050 ti oc edition and xeon 3460 and 4 gb ram 2 slot , i installed it. And everything works fine , after upgrading everything , i went to dxdiag , and 8 gb ram and gtx 1050 ti and xeon are all successfully upgraded , so after that , pc randomly start restarting by it self , and they asked me about repairing, so i repair the pc and thats fine , after that i went to dxdiag to see all things normal , now i have an 4 gb of ram not 8 gb ram , and the pc restart randomly i dont know whats wrong , really good help for you would be amazing ,
Spec
Cpu xeon 3460
Mobo intel dh55hc
Psu thermaltake 550w
Gtx 1050 ti oc edition
Ram.8 gb

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