Fan stepping. The CPU/GPU fan starts at 3400RPM - that's quite a noisy lowest speed, and it's almost the same sound as the 4000RPM following. In an office environment, it's clearly conceivable. On my X220 and similar laptops, the slowest fan speed is a lot less noisy. Furthermore, running the fan at this speed seems quite pointless at 41°C temperature. I'd love to see a BIOS update introduce a calmer low RPM fan level.
Lenovo's engineering team released a BIOS v2.52 which addresses the Fan issue. Please click the link below or go to the Lenovo support page http://support.lenovo.com to install this version of BIOS or later.
BIOS Update (Bootable CD) for Windows 8 (32-bit, 64-bit), 7 (32-bit, 64-bit), XP - ThinkPad T430, T430i ... Learn more