Since the fan is internal, Asus has put marked the top of the Lion Square with an arrow to show you wish way airflow is going. Since the Lion Square is more oval in shape, you shouldn't have any problems getting this to line-up with the exhaust fan in your enclosure.

For us folks mounting the Lion Square to the Intel bracket, we'll find those bevels in the fin array very welcome indeed. The bevels allowed Asus to maximize fin density while still allowing easy installation and removal.

Testing

The Asus Lion Square will be tested with the following components. 

OCCT version 2.0.0a will be my tool of choice, letting the stress test run for one hour with the CPU at its default clock (3000MHz) and voltage (1.225 volts) settings. O.C.C.T. begins its test by monitoring the system under idle conditions. The test was conducted with an ambient temperature of 72.7*F (22.6*C) with the side panel closed on the Ultra m998 enclosure. One thing to note here, the Asus Lion Square is tall, but would still allow the vent fan to be installed on the enclosure panel of the enclosure. Some heatsinks are quite large, and would not have that kind of clearance. Either way, the vent fan was left off for the duration of this test.

Intel E8400 (Core #1) @ 3.0Ghz

Intel E8400 (Core #2) @ 3.0Ghz

The above charts show Core #1 and Core #2 starting their idle run at 36*C. They heat up quite quickly to an average of 52*C and never peak higher than 54. Once the test is over at the 54 minute mark, O.C.C.T. reduced the CPU load to 0% and continues to monitor the core temperatures. We can see the Asus Lion Square recovers very quickly, cooling the CPU to 35*C.