Intel 3.40E & 3.40C Pentium 4

..:: Introduction ::..

A little over two months have passed since the rather quiet release of Intel’s latest Pentium 4 Processor core, code-named “Prescott”. The “Prescott” chip was actually released several hours earlier than the typical Intel release times, and ended up falling on Super Bowl Sunday. With all of the build-up of bad karma following “Prescott” before launch with rumors of delays due to heat output, outrageous TDP numbers, and more, it came as no surprise that Intel would attempt to launch the “Prescott” core quietly, and this fact can be seen by the fact it was launched early, on a Sunday, on Super Bowl Sunday. The rumors about the high TDP numbers for the “Prescott” core turned out to be true, and we noted some high temperatures during our testing period with the 3.20E processor. In comparison to the 3.20C, we found the 3.20E to be a bit lacking in performance, and a little heavy on the heat output. Today, we’re going to take a look at the recently released 3.40C and 3.40E to see if the added MHz can help “Prescott” catch up some more to the “Northwood” processor. We’ll also delve further into the heat issue with some interesting temperature measurements to help illustrate it.


..:: 3.40C & 3.40E Official Specifications ::..


..:: “Prescott” Core Heat Issues ::..

As we saw with the official TDP ratings for the 3.40E and 3.40C processors, the 3.40E is going to put out a substantially larger amount of heat, much due to the increased current needed to run the processor, especially at full load, along with the increased current through the same number of power pins in the processor package, and of course, the more than doubling of transistors in the processor core. It is no secret now that “Prescott” is quite the hot chip, and that those looking for quiet cooling are going to want to stray away from the “E” processors until Intel can find a way to “solve” the heat output problems. Why do I put solve in quotations? Simply put, the amount of transistors and current needed to run the processor pose a serious problem. Intel needs to develop further manufacturing and design techniques in order to advance in the race for a cooler running chip. There is no simple overnight cure for this type of problem, so for all of you looking for Intel to come up with some magic cure than takes the TDP down a good 20W, you need to come back to reality.

For now, we’re stuck with a chip that runs quite warm, and several motherboard manufacturers have begun to take a less than positive stance against it as well. Soltek recently released their VIA PT880 based motherboard that we reviewed, and informed us that they would only officially support the “E” processors up to 3.00GHz. Their reasoning? Heat, Heat, Heat. MSI is also widely known to disallow VCore adjustment when it comes to the “E” processors due to their dynamic VID feature. I have discussed this heat issue with several first and second tier manufacturers, and nearly all of them have stated their unease with the heat levels of “Prescott.” The problem with heat is the effect it has on the core components of the board itself. The excess heat puts undue strain on capacitors, transistors, resistors, etc. Each of these electrical components reacts in unfriendly ways to increased heat, and can have their life spans shortened due to it. While we have yet to experience any instabilities due to the heat that is output by the “Prescott” processor, even with a stock Intel cooler which by the way performs quite nicely for the noise level, they cannot be ruled out for some other possible problems that could creep up with the increased heat output and strain placed on the motherboard components.

What kind of heat levels are we talking about? Well, we decided to try to get a relative temperature difference between two identically clocked “Northwood” and “Prescott” core processors to see just how much extra heat “Prescott” is putting out. In order to do this, we placed both chips in a cased situation, and put them in a bit of a torture state with no incoming or outgoing fans for airflow. While this can’t mimic the worst situation, it certainly won’t make things easy for either processor to run cool. In order to give you more accurate results as to the performance many of you will see, we chose to use the stock cooler than Intel provided for the 3.20E and 3.40E samples. While this cooler may look simplistic, it is capable of providing some excellent cooling for both the weight, and noise level. In order to acquire temperature readings, we took a thermal probe from one of our spare 5.25” drive bay devices. We cut down the excess plastic material around the tip of the thermal probe, and placed the tip of the probe against the side of the Pentium 4’s heatspreader. While this won’t be the hottest place on the chip given that by the time the heat energy has reached this point it will have lessened to some degree, it is still able to give a relative ratio of temperatures between chips. The results we achieved for our 3.40GHz models can be seen above. With an ambient temperature of 22.8C (73.0F), we found the “Northwood” core to run 8.3C (15.0F) cooler at idle, and 9.5C (17.1F) cooler under full load. These numbers easily illustrate the heat output of the “Prescott” core.