The cross-load diagram of the junior model doesn’t look neat due to the stable, but consistently too high, +3.3V voltage. The +5V voltage is also too high when the load is misbalanced towards the +12V rail as is typical of the modern PC.
The senior model looks somewhat better but the +12V voltage bottoms out slightly under load.
The output voltage ripple is within the norm, although very close to the limit on the +3.3V rail.
Each PSU uses a 120x120x25mm fan (Yate Loon D12SH-12).
The fan has a constant speed at low loads but accelerates after a certain threshold. Like the Hercules AX400-PN, the Extreme series models are average in terms of noisiness. The fan is quite audible at 1200rpm.
Alas, the AX450-PN would shut down after working for 3-4 minutes at a load of 375W although its continuous load is declared to be 400W. Perhaps Tsunami uses a 350W rather than a 400W unit from FSP for its AX450-PN because I didn’t see PSUs sold under FSP Group’s own brand behave like that.
The efficiency is slightly above 80% while the power factor barely notched 0.65.
So, the Extreme series only differs from the Hercules with the color of the housing and the availability of a 400W model. Unfortunately, the company didn’t make the cables longer or increase the amount of connectors. The rest of the characteristics are identical because both series are based on the same PSUs manufactured by FSP Group.