I never benching at ambient <20°C. My city at all weather never went 18°C, even 22-24°C is very rare. On my 7700K im at 30°C ambient did 5.3-5.4ghz 05 and at 20°C ambient with strong Air Conditioner, can R15 at 5.3/5.4GHz, XTU 5.25ghz and 05 5.5ghz. I cant imagine if i go below 10 or 0 ambient. Thats why make 2 Water Categories :
>0°C Enthusiast (Warm Water)
<0°C Apprentice (Cold Water)