NP. I was going to say, only need to drop another 5C to crack 15k. Just crank down the A/C or run a duct from a vent.
Which block do you have? My Heatkiller V is around 10-12C block delta (water to core) at 450w. I give a range because it will vary depending on where the power is going (mem vs. core mostly). 38C average is good, so I doubt you're leaving much there.