Intel's Pentium 4 E: Prescott Arrives with Luggage

Availability, Yields and Overclocking

Intel’s 90nm fabs are working hard at cranking out Prescotts as fast as possible, but as is the case at the start of any ramp there will be supply issues. We are hearing that widespread availability of chips in the channel for people like us to order won’t be until March 1st, although you should be able to find OEMs with systems available immediately.

We are also hearing from reliable sources that the current steppings of Prescotts coming out of the fabs are performing very well. To get an idea for what sort of headroom to expect we conducted some informal overclocking tests on our Pentium 4 3.20E that we had for testing.

We conducted all tests using just air cooling and we kept the CPU voltage at its default of 1.385V:

An effortless overclock gave us 3.72GHz; we could POST at 4GHz but we didn’t want to showcase what was ultimately possible with Prescott, rather what was easily attainable without increasing voltages.

Intel could have launched Prescott at higher clock speeds than they did, however it seems that their desire to produce as many mainstream Prescotts as possible (2.80E in particular) won out in this case.

Update: Intel has released the official thermal data on Prescott:

As we mentioned before, if you thought Prescott was going to be cooler running you'd be wrong. Prescott is one hot running CPU, now keep in mind that these aren't actual production thermals rather Intel's guidelines to manufacturers as to what thermals they should design cooling for. Needless to say, Prescott at 2.8GHz will be about as hot as a 3.4GHz Northwood. When Intel ramps up beyond 3.6GHz we'll definitely see some larger heatsinks being used on Pentium 4 platforms; some of the preliminary cooling setups we've seen for Tejas were insane.