NASM 2.05 based x86 Instruction Reference[ch146]
A.5.125 INVD: Invalidate Internal Caches INVD ; 0F 08 [486] INVD invalidates and empties the processor's internal caches, and causes the processor to instruct external caches to do the same. It does not write the contents of the caches back to memory first: any modified data held in the caches will be lost. To write the data back first, use WBINVD (section A.5.328).