Ivy Bridge Configurable TDP Detailedby Anand Lal Shimpi on September 12, 2011 2:28 AM EST
At Computex Intel announced that Ivy Bridge would be its first processor to support a configurable TDP. Today all CPUs are rated at a single maximum TDP. Mainstream notebook processors fall in the 35 - 45W range, while mainstream desktops are around 65W. As the world embraces mobility and interfaces like Thunderbolt enable new usage models for notebook users (e.g. docking station with a beefy external GPU), Intel had to rethink its power strategy.
Today with a 35W CPU, Intel guarantees the OEM that if it implements a chassis and cooling system capable of dissipating that much heat the chip will operate as intended. If the OEM offers an optional dock or high-performance cooling mode that could cool a higher wattage chip, the CPU can't take advantage of it. Ivy Bridge changes this.
Ultra low volt (ULV) and extreme edition IVB parts will carry three TDP ratings: nominal, a lower configurable TDP (cTDP down) and an upper configurable TDP (cTDP up). Let's talk about cTDP up first.
ULV Ivy Bridge parts will be rated at 17W, similar to the ULV SNB CPUs that are used in Ultrabooks and the new MacBook Air. Intel will also guarantee these chips at a higher frequency with a TDP of 33W. If the Ivy Bridge MacBook Air could dissipate 17W of heat normally but when placed on a docking station with additional cooling capabilities could remove 33W of heat, the CPU would simply run at a much higher frequency when docked. This goes beyond simple turbo as it exceeds the CPU's nominal TDP, whereas turbo mode is mostly bound by TDP.
The same applies in reverse. If you want the chip to behave as if it were a 13W part instead of a 17W part, that will be possible as well. It's configurable performance based on the current conditions. If you have tons of cooling ability, you get more performance. If you need battery life, you get a chip that makes your system behave like an ultraportable.
The extreme edition IVB parts will also support configurable TDP. 55W parts will be able to go up to 65W or go down to 45W.
You can expect that Intel will use configurable TDP as a reason for customers to buy the more expensive versions of Ivy Bridge. Ivy Bridge is expected to arrive on notebooks and desktops in April - May 2012.