Not sure, it is a new processor so CPU-Z may not yet be updated to identify it correctly.
The SI-42 is single core 2.1GHZ, 512k L2 cache, Sable core.
I'm only guessing the SI-46 is with he newer core Griffin, perhaps with a better memory controller( and 45nm SOI?).
Try also Native Specialist and cbid, what they say about the proc.
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