You mean 5,9cm with fans? But it needs at least 3cm over it to suck in air, and a few cm under to spitt it out. So 10cm wouldn't be too bad? 30mm with air in + 25mm FAN + 34mm Swiftech Rad + 20-25mm air out = ca 115mm... Actually its more than 10cm, about 11-12cm. But I guess I don't need 30mm with air in, but it shore helps. A HW Lab Rad will give me 0,5cm better space... I'll have to think a bit more... or use the slim rad. Thank you for helping!