Does Non-Temporal Load/Store Hints have different behavior for WC, WB memory type?

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Does Non-Temporal Load/Store Hints have different behavior for WC, WB memory type?

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I'm a little confused about the Non-Temporal hints as below, could any expert help to give some comment?

Non-Temporal hints is used for scenario where data maybe used only once. it could help to avoid cache pollution.

But:

1. From <<Intel software develop manual>>, it seems that Non-Temporal hint are mostly apply to memory region of WC(write combine) type, but WC type is inherently un-cacheable. why we still need NT hints ?

2. What's the detail behavior when we use NT hints to load and store.

3. What's the difference when the target memory type is WB and WC?

Ref:

1. Intel SDM volume2, movntxxx instruction description.

2. https://software.intel.com/en-us/forums/intel-isa-extensions/topic/597075

3. I also do some experiment on i5-2400 for WB memory type, it seems that NT store hints work as desired, but NT Load have no effect.

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