hi, new guy here with a cooling question

[Andyelmoblack]

hi, please bear with me, im new here and new again to the building of pcs. i've built myself a pretty reasonable pc for playing a few games but mainly to aid in my hobby of 3d printing. it's been over 20 years since i built a computer but it hasn't really changed, one thing im unsure on is cooling, ive built my computer into a custom designed tv stand as we use it mainly for modelling it helps to have a big screen. 

specs:

Mboard asrock b450 hdv r4.0

CPU ryzen 5 2600x (stock cooler)

Ram ballistix 16gb ddr4 2666

Gpu msi rx 570 armor (arctic cooling cooler)

m.2 256 sabrent and a 1tb western digital blue 

The enclosure has a front intake fan blowing directly over the cpu and cooler and an exhaust fan blowing out the back, the psu is located below everything with its own air flow. im wondering if i should be concerned as im seeing temps on the cpu jump around from 29-47 degrees when sat idle, the gpu is great, running dirt rally 2.0 at high 1440p it barely reaches 70 degrees. is this abnormal or am i concerned over nothing and just out of touch lol cheers for any help 

[boggy77]

7 minutes ago, Andyelmoblack said:

29-47 degrees when sat idle

that's ok. do a stress test or a cinebench run. if the cpu doesn't go above 85C, it's fine

[Andyelmoblack]

so , at the risk of sounding dumb, whats the best test to run?