After ram installation computer keeps restarting

[LDancer]

So I decided it was time to get some new ram so I got two new hyperX fury dimms (both 4gb), these are both exactly the same as the ram I had before. After booting the system after two seconds it would restart. Can someone help me fix this issue?

i7 4790k
8 gb ddr3 ram hyperX fury
Corsair 550 watt power supply
Msi z97 g43 motherboard

 

[GhislainG]

Did you lower the frequency, loosen timings or increase voltage a bit? You usually can't run 4 modules at the settings used with 2 modules. Modules are guaranteed to be identical only when bought as a kit.