The Move To BTX: A Case Of Cost

In the short term, pricing for cases likely would increase as cabinet vendors seek to recoup the cost of retooling. And in the long term, cabinet prices could remain slightly higher as the BTX standard makes the cabinet responsible for more of the system's heat dissipation. So the higher price of BTX cabinets, coupled with a reduction of ATX cabinet prices to flush out inventories, may stall the new form factor's adoption in the market.

Still, BTX is a necessary step to address the challenges of heat and noise in Intel's evolving desktop processor line, and it's important for system builders to understand those benefits to explain them to customers.

The BTX design--available in small, medium and large sizes (PicoBTX, MicroBTX and BTX)--moves the processor-cooling fan to the front middle of the PC cabinet and relocates motherboard subsystems from the positions they normally occupy in an ATX system. Shifting the processor fan to the center of the front panel allows a larger, lower-RPM fan to be used, reducing noise.

BTX also calls for a new noise-reducing fan cowling. A sleeve around the cowling aims cooling air over the processor heat sink before the air travels further into the cabinet. As a result, the processor receives cool air from directly outside the cabinet.

With BTX's redesigned and realigned fan assembly--as well as the new positions for the memory, video card, north bridge and south bridge--the fan can perform a dual role by cooling the processor and other components. Such zone-based thermal management is similar to the design of Apple's Power Mac G5.

Yet simply rearranging the motherboard components to align them with the new fan would make motherboard circuit-routing difficult. So to ease motherboard design, Intel also swapped the positions of the back-panel connectors and the adapter card slots.

The changes BTX brings to the back panel, along with its shift of the thermal solution to the case, account for the increased case costs. Though it's likely that some BTX systems will appear around the holidays for the enthusiast market, they probably won't be seen in businesses until months later in 2005.

What do you think about Intel's planned transition to BTX? Let me know via e-mail at [email protected].