I have a Dell Precision M70, which is of similar form factor to the i6000, but has a much more powerful gpu (256MB Nvidia QuadroFX Go 1400) compared to the i6000's X300. Of course such a gpu creates more heat. However the M70 (and its sister, the D810, which has a X600 as its gpu) has more heat vents and a separate fan for the gpu as well as the cpu. Running i8fangui in observer mode, the cpu temperature travels between 39 and 54C, the gpu from 52 to 60, and the HD from 40 to 41. Some fan is always on but very quiet, and when the cpu or gpu temperature hits the top mark, it gets just a little louder, forcing the temperature back to the lower level. A very pleasant machine to work with, and very quiet, considering the powerful gpu. At least on the top of the notebook, it is always cool. The M70 takes the most demanding programs in its stride, never struggling.
Dell Precision M70, Pentium M 750 (1.86MHz), 256MB Nvidia QuadroFX Go 1400, 1024MB 533MHz DDR2, 60G @ 5400RPM, WUXGA 147 ppi set at 120 ppi.