Why MIG instances can only sum up to 98 SMs instead of the 108 SMs available?

Hi Community,
Just as the title says, any know why MIG instances can only sum up to 98 SMs instead of the 108 SMs available in the A100 Tensor Core GPU Implementation (NVIDIA Ampere Architecture In-Depth | NVIDIA Developer Blog)? Any explanation is welcome. Best

āžœ  ~ sudo nvidia-smi mig -lgip
+--------------------------------------------------------------------------+
| GPU instance profiles:                                                   |
| GPU   Name          ID    Instances   Memory     P2P    SM    DEC   ENC  |
|                           Free/Total   GiB              CE    JPEG  OFA  |
|==========================================================================|
|   4  MIG 1g.5gb     19     0/7        4.75       No     14     0     0   |
|                                                          1     0     0   |
+--------------------------------------------------------------------------+
|   4  MIG 2g.10gb    14     0/3        9.75       No     28     1     0   |
|                                                          2     0     0   |
+--------------------------------------------------------------------------+
|   4  MIG 3g.20gb     9     0/2        19.62      No     42     2     0   |
|                                                          3     0     0   |
+--------------------------------------------------------------------------+
|   4  MIG 4g.20gb     5     0/1        19.62      No     56     2     0   |
|                                                          4     0     0   |
+--------------------------------------------------------------------------+
|   4  MIG 7g.40gb     0     0/1        39.50      No     98     5     0   |
|                                                          7     1     1   |
+--------------------------------------------------------------------------+
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