It's just a bug in the Everest program that was confirmed a while ago. Look at RivaTuner under Diagnostics:
$ffffffffff NVIDIA specific display adapter information
$ffffffffff ---------------------------------------------------
$0100000000 Graphics core : NV40 revision A1 (16x1,6vp)
$0100000001 Hardwired ID : 0041 (ROM strapped to 0041)
$0100000002 Memory bus : 256-bit
$0100000003 Memory type : DDR (RAM configuration 06)
$0100000004 Memory amount : 131072KB
$0100000005 Core clock : 327.857MHz
$0100000006 Memory clock : 425.250MHz (850.500MHz effective)
$0100000007 Reference clock : 27.000MHz
$010000000b HW masked units : pixel 0010b, vertex 000010b