Sliding off the large side panels (secured by a pair of plastic-grip thumb screws) reveals that the P280 has largely done away with the compartmental design ethos of its predecessors. Instead it uses a large central compartment for both motherboard and PSU, and it certainly is extremely spacious. While falling short of E-ATX, the motherboard mounts support up to XL-ATX (345mm x 262mm) motherboards and four huge cable routing holes around the motherboard tray make cable routing straightforward.
Click to enlarge - A spacious interior abandons the P180's compartmental design
The routing hole’s rubber covers aren't glued in place, but are securely fitted enough to survive our man-handling of PSU cables through them without issue, and the case’s extended width means there’s a great deal of room behind the motherboard tray to tidy even thick 24-pin ATX cables away. There’s also a gigantic motherboard tray cut-out to aide in the installation of back-plate mounted CPU coolers.
Click to enlarge - There's lots of room behind the motherboard for cable routing
3.5in hard disk drives are mounted in a dedicated perpendicular rack to the front of the case. The rack is static, and this limits the P280’s maximum GPU length to 330mm – still more than enough for even the biggest graphics cards. Drives are mounted into individual mount-trays using screws and silicon vibration dampening grommets, with each tray also including mount points for 2.5in drives. Two dedicated 2.5in drive mounts sit above the 3.5in mounts, with the three external 5.25in drive mounts at the top of the case. The latter are fitted with excellent tool-less fittings that automatically click into place when you slide in a drive.
The P280’s three exhaust fans surround the top left corner of the motherboard tray, but are joined there by an oddly placed Molex to 4 x 3-pin fan header. This is the power point for the three case fans (but does not control their speed)) and is placed right above the rear exhaust fan. As such, fitting liquid cooling kits such as the Antec’s own H20 920 or Corsair’s H80 can obscure access to the fan headers. While you can flip the header to improve access, we’d just as soon not use it at all and route the three 3-pin power cables behind the motherboard tray, although this would require some Molex to 3-pin adapters.
Click to enlarge - The three cooling fans and 3.5in drive bays; note the Molex to 3-pin fan connector just above the rear exhaust.
While the pair of roof 120mm fan mounts will support half-height water-cooling radiators such as that used by Corsair’s H100 CPU cooler, bespoke water-cooling enthusiasts will be disappointed to find that a full-height radiator just won’t fit. This is particularly disappointing as the case’s nine expansion slots mean there’s a great deal of space beneath the motherboard, but not above it.