Hi Guys, my pc keeps rebooting. pc is newly built, all new parts except the psu (550w corsair-about 4 years old). Started about a month ago, it would randomly reboot every 10-15 mins and got progressively worse over 1-2 days until it rebooted every 1-2mins & i couldnt even access the bios. i re installed windows 10 which fixed this issue for about a month.

this weekend it stared rebooting again. i tested the graphics CARD by switching it out with an old one, no luck. i switched the ram to different slots(dont have any spare to test) i had a spare hd in there (which wasnt being recognized- i didnt even realize as i didnt use it) as soon as i removed it, the reboot loop stopped.My pc case is the thermaltake level10 gt, it has a bunch of built in HD slots & it was attached to one of those. it stopped the reboot loop for 2 days and now its back to rebooting every 5 mins.

Is it likely the psu or motherboard?

Here are my pc specs:
http://speccy.piriform.com/results/Dq0IN6Dnmo802Lp5oISsTzr


ive found this too, if this helps at all:

Index : 1031
EntryType : Information
InstanceId : 2147484722
Message : The process C:\Windows\System32\RuntimeBroker.exe (DESKTOP-EAQN702) has initiated the power off
of computer DESKTOP-EAQN702 on behalf of user DESKTOP-EAQN702\Zan for the following reason: Other
(Unplanned)
Reason Code: 0x0
Shutdown Type: power off
Comment:
Category : (0)
CategoryNumber : 0
ReplacementStrings : {C:\Windows\System32\RuntimeBroker.exe (DESKTOP-EAQN702), DESKTOP-EAQN702, Other (Unplanned),
0x0...}
Source : User32
TimeGenerated : 5/12/2020 5:48:19 PM
TimeWritten : 5/12/2020 5:48:19 PM
UserName : DESKTOP-EAQN702\ZanHi

Checking the speccy report i SEE this is a new install of windows 10 installed on the 4th Dec 2020. It is most likely the power supply although the  GeForce GTX 1660 SUPER
should work with a 450 Watt power supply it is the only not new component. After windows has CRASHED like this it would pay to reload windows again after you get a new  supply.