Stealing slots?
Because the ZM80A-HP relies on passive cooling, it needs more surface area than your average GPU cooler to pull heat away from the graphics chip adequately. All that extra surface area makes the ZM80A-HP massive by today's standards, but the cooler creates fewer clearance problems than one might expect.

It looks big, and it is

Before I get into clearance issues, it's important to note that the ZM80A-HP weighs nearly 400 grams, which is quite a bit heavier than the average graphics cooler. An AGP slot retention mechanism is all but essential to ensure that the cooler's weight doesn't help unseat the graphics card when a system is moved. With careful transportation, a securely-attached cooler and graphics card should survive multiple LAN party trips, but it's a good idea to be extra gentle.

Plenty of DIMM and chipset cooler clearance

Though the ZM80A-HP adds a lot of height to the back of an AGP card, there's still plenty of clearance for DIMM slots and large north bridge coolers. Even the tallest of motherboard capacitors are well clear of the rear passive heat sink.

Some motherboards won't even lose a PCI slot

Depending on the motherboard, the ZM80A-HP may not even rob users of a PCI slot. As you can see here, there's plenty of room between the front passive heat sink and the AT7 MAX2's closest PCI slot. The ZM80A-HP will, however, create clearance problems for the first PCI slot on many motherboards. Small form factor PCs like Shuttle's XPC series are also incompatible with the ZM80A-HP without extensive case modifications.