Translated version of an article reporting that Prescott power consumption is 15% over design spec typical power 103watts instead of the 89 the design called for:
Link from this inquirer story:
theinquirer.net
PDF of graph is here:
pc.watch.impress.co.jp
It was hot after all the Prescott
The Intel, 2 types throws the CPU of the next generation production process 90nm, within year. 2nd generation Pentium M of the schedule which is announced to around the end of 3rd quarter " Dothan (the ƒhƒ^ƒ“)" with, " the Prescott (the press cot)" of the Pentium 4 succession which is thrown during 4th quarter is. The Intel, it throws the Prescott within year first with the 3.4gHz, next year 1st quarter pulls up to the 3.6gHz. As for the Prescott verification of the sample has been advanced already, the Intel is advancing the preparation to sale favorably. It was the expectation which well, is being advanced favorably.
Falling to there, those where it boils, are thermal problem of the Prescott. Electric power consumption of the Prescott, being higher than Intel itself expectation substantially was ascertained. Somehow, the TDP of the Prescott (the Thermal Design Power: Thermal design electric power consumption), it exceeds the mark of the 100W finally at frequency of the 3.6gHz, it seems. Because expectation of the Intel of beginning was the 89w, it means that as many as 15% increased at a stroke.
Because of that, the Intel has begun the specification modification of the Prescott corresponding motherboard. As a result, even with the present Intel 875/865 motherboard which is assumed it can correspond to also the Prescott, the case which it cannot correspond to the Prescott coming out, you rival, is. As for being more painful, with the note PC which loads the Mobile Prescott which appears in the next year head, considerable influence probably will put out, is.
In addition, in the long term, as for this case the fact that the brake is not applied to the increase of electric power consumption of Intel CPU, is hinted. If it becomes so, the PC becomes something which more and more the design and the original work are difficult to do. Furthermore, 90nm process of the same company, has suggested also the possibility electricity consumption being more than schedule.
- It has an influence on the FMB guideline the TDP of the Prescott which
The Intel before usually, actual electric power consumption measures with the sample tip/chip, conveys expectation electric power consumption to the OEM vendor. This fine control being in order the corresponding motherboard preceding, to have designing, after that, electric power consumption and product plan of the actual sample tip/chip (it commercializes to no GHz) together. This is usual pattern, but as for those where this time it is different, electric power consumption with the pre- silicon and the post silicon to be large is to slip.
Actually, as for at this story from about 1 - 2 months ago in PC industry it seems that is known. According to that, as for the Intel, being maximum, you estimated the TDP of the Prescott of the mu PGA478 package it is the 89w, you say. However, as for the result and this numerical value which advanced verification with the actual silicon it was rewritten in the 103w. When electric power consumption increases, you must increase either the quantity of the electric current which is supplied to the CPU. Because of that, the supply electric current to the CPU on the motherboard (the IcccMax) it was increased to the 91a from the 78a. In other words, as for the motherboard which cannot supply that much electric current quantity, it comes to the point of not being able to correspond to the Prescott.
- With Prefetch architecture to many fold
Extension of TDP of Intel CPU
As for PDF edition this way
The Intel, guideline " Flexible Motherboard of the motherboard design which is offered vis-a-vis the OEM vendor (the FMB)" influences this problem, largely. The Intel offers the FMB of 2 types to every each CPU generation. For example, present 0.13 mu m edition Pentium 4 (Northwood: The north wood) vis-a-vis, there is a " Northwood FMB1 " and a " Northwood FMB2 ".
Those where it corresponds to the Prescott when with the " Prescott FMB1 ", it conforms to this, had come to the point of being able to support the both of the Northwood and the Prescott. Those which already have conformed to these specifications they are many expectations in the motherboard.
The William M. Siu of the Intel (the ƒEƒCƒŠƒAƒ€ * M * sou) the vice president and the general manager (the Vice President and General Manager, the Desktop Platforms Group) you explain as follows concerning the Prescott FMB1.
" (The Prescott) the FMB1 is the design which in the customer from the Northwood makes the movement to the Prescott possible. When movement of the CPU socket and tip/chip set accompanies (the movement of the CPU), it cannot move the customer easily rapidly. But, in case of the Prescott as for big modification there is no necessity (in the motherboard). Therefore, movement to the Prescott it is rapid, thinks "
With the Prescott FMB1, the EOL (last edition) to the Northwood (the 3.2gHz) with, it corresponds to the Prescott of mu PGA478 edition. The Intel has been about on to move with the Prescott the 3.6gHz compared to the new package LGA (the Land Grid Array) 775 ƒw. In other words, with the Prescott FMB1 it means to be the schedule which it can correspond to the Prescott to the 3.6gHz. By the way, it has become the schedule which generation CPU " Tejas (the ƒeƒnƒX)", corresponds with the Prescott of the LGA 775 generation one after another with the Prescott FMB2.
However, because the TDP of the actual silicon of the Prescott rises too excessively, as for the Intel when plan is changed, forcing. According to a certain information muscle, you say presently the Intel having decided and offering the Prescott FMB1.5 of the correction edition specifications. When with this Prescott FMB1.5, the TDP the 103w and the IcccMax approximately 15% is increased to the 91a, forcing. The fact that another specifications, FMB1.5 were made, because modification is large, is the case that the necessity to divide the FMB specifications arose. Somehow, unless it is the motherboard of Prescott FMB1.5 conformity, the Prescott seems a story that it cannot support.
Because as for influence to the FMB being large, it is difficult already to stabilize to supply the heavy-current quantity even under present conditions through the motherboard. This is entwined closely with cost. The present Voltage Regulator Modules of the Intel (the VRM) specification, stabilizing, can supply heavy-current has become " VRM 10.0 ", with VRM 10 multiple phase is supported. And, the Intel, is said at the beginning, with the Prescott FMB1 3 phases, 4 phases were required with the FMB2. But, really you call 3 phases it was not excessively accepted in the cost aspect. Is, it is said, but because the TDP keeps rising, in the future quickly the necessity to increase the number of beam phases probably will arise.
- The head is painful the TDP of of 100W over
Another problem, until you say, is the thermal design with rise of the TDP without. Usually, when the TDP rises, furthermore it becomes troublesome to cool the CPU. However, this time the TDP of the Prescott rising, the heat sink and the Ta (basket internal temperature) the specifications without modification call the Intel it can go, it seems. In other words, the case that it is not necessary, for the CPU to change cooling into becoming hot, it is. The seed of this magic is simple. As for the Intel the Tcase (the package temperature of the CPU) it modifies.
In the thermal design of the PC, it becomes the element whose temperature difference of the air of the CPU and basket internal and the electric power consumption of the CPU, and heat resistance value of the heat sink are important. Concretely, (the Tcase - the Ta) the €tdp = heat sink (the + thermal interface material) heat resistance value, with it becomes.
The among these, heat resistance of the heat sink is restricted first. If heat resistance value is displayed with the degree C/W and value is small, small extent it is superior, but cost becomes high. Technological progress of the heat sink pace is slow, presently 0.33 degree C/W with the PC is made the limit.
On one hand, temperature of basket internal is shown " the Ta (the ambient)" with. If it is low, the thermal design of the around low extent CPU becomes easy, but that much, technology in order to reduce the temperature of basket internal becomes necessary. For example in the past as for the Ta 40 - 45 degrees C (, the Northwood FMB2 was 42 degrees C), but with the present Prescott FMB1 it has become harsher than 38 degrees C. Also these specifications, will lower the above this, but it is in a state where it is not.
With being the case that it is said, in the circumstance where two elements are fixed, one parameter changed. So when it does, if one parameter which naturally, remains is not changed, it does not consist. In other words, amount and the Tcase where the TDP rose were pulled up. As for the Tcase of the Prescott of the time before those where they are 69 degrees C, with 1.5 have reached 74 degrees C. Actually Tcase rise ratio is smaller than ratio of TDP rise, but that is thought is, because the FMB1 room was seen. That this measure influences it is thought it is yield rate and the like of the Prescott. In other words, the development whose are inconvenient for the Intel it is reason.
But, the desktop still is better one. As for problem, the Intel desktop replacement (DTR) must throw the Prescott to also the note PC. Because for the DTR substantially is the TDP of the same level as the desktop, it has become very troublesome circumstance.
To recently the TDP of the Mobile Prescott was the 74w with the 3.46gHz. Is, but presently, as for the TDP of the Mobile Prescott you say it has become the 94w. With note PC 94w! Some DTR say, as for this it is considerable challenge.
The Intel even with Mobile assures the solution by the fact that the desktop in the same way the Tcase is pulled up. The Tcase of the former Mobile Prescott was 72 degrees C, but now this has reached 76 degrees C, it seems. But, because even then it is not enough, with the DTR also the Ta 5 degrees C seems that is lowered. In other words, as for the note PC designer, you do not think of the waste heat mechanism which 5 degrees C in temperature of basket internal can reduce from so far it is the case that it becomes necessary.
With being the case that it is said, the " hot Prescott " has started bringing many distortion. Though, the Intel measure seems that is doing. There is also information that release it does the Prescott which can be supported even with the Prescott FMB1. Although the Prescott of the high clock is supported with the FMB1.5 you held down to the TDP of the range which can be supported with the FMB1, it is a story that it puts out also the Prescott where the single step clock is low. But, as for details it is not found yet. |
