You’re looking at about a half hour per kilogram of copper to raise it by 50 °C with 100W of heat.
Actual delta from ambient to thermal limit will typically be a little higher than that, but so is processor wattage on mid-to-high performance CPUs, so I’m happy enough with that as a ballpark estimate.
Someone else estimated that block as 4.5kg, so you’ve got something close to two and a half hours of cooling from an ambient start.
You’re looking at about a half hour per kilogram of copper to raise it by 50 °C with 100W of heat.
Actual delta from ambient to thermal limit will typically be a little higher than that, but so is processor wattage on mid-to-high performance CPUs, so I’m happy enough with that as a ballpark estimate.
Someone else estimated that block as 4.5kg, so you’ve got something close to two and a half hours of cooling from an ambient start.