I bought a used HD750.  The documentation online is ambiguous on whether or not connecting a single 8-Ohm cabinet is safe.

1.  From the Lowdown Manual: 

Warning!

Only use a 4 Ohm speaker cabinet when running in

mono. Only use 8 Ohm speaker cabinets when feeding

a pair. Warning! Do not plug two 4 Ohm cabinets

into either the HD400 or HD750 as it can result in

damage to the amplifier.

I want to plug in  my single GK 8-Ohm 2x10 cab (rated at 400 watts).

Will that harm the amp?

2. From the Lowdown FAQ:

***Connecting a single Line 6 LowDown cabinet (8 ohms) to the LowDown 400/750

HD single 4 ohm output cuts the power output to the cabinet in half.  375 watts from the

LowDown 750 HD, and 200 watts from the LowDown 400 HD.

Does this mean plugging in a single 8-Ohm cabinet is safe because the HD750 will only output 375?  Will it start smoking?

Thanks!