Intel P35/G33 - DDR3 or optimizations memories?

[Jeffrey]

1. INTRODUCTION

Whereas usually the board manufacturers mothers are the first to be complained about the lack of time left by the manufacturers about chipsets, and Intel in particular, between the specimens of pre-production and the official date of launching, P35 and G33 derogate from the rule. Announced for a long time, these Bearlake have been indeed already available in certain stores for several weeks, whereas Intel envisaged a launching only for Computex (at the beginning of June). The manufacturer thus decided to create an earlier date of embargo with regard to information on the chipsets, today, and which is thus rather artificial. One is enough far from the rather usual situation where only Intel and Asus are capable to provide boards to the press and the stores the day of launching.

Paradoxically, the arrival of these chipsets is far from pressing insofar as we will see it, the list of the innovations whom they introduce is relatively limited and which they relate to mainly new Core 2 Duo FSB 1333 MHz, which will arrive for their part only on July 22, to see the processors 45 Nm (Penryn, that is to say the end of the year for the first versions). Preview of the successors with the P965/945G.

A corner of the veil only

Only part of the chipsets Bearlake are launched and available today: P35 and G33. The complete range does not contain indeed less than 7 chipsets, whose in particular X38 and G35 which should prove to be most interesting, but which will be available only to the third quarter (probably on July 22, like new processors).

The large innovation introduced by these chipsets, namely the support of the DDR3, is limited however to G33, P35 and X38, whereas important limitations are to be noted side of G31, chipset of entry of range limited to antique ICH7 (but supporting at least a port IDE!). G35 (official successor of G965) will be also limited to the ICH8 what is rather illogical insofar as this chipset seems to be the only one to support a new graphic circuit DirectX10, X3500, and is thus located above G33. It should be noted that X38 will have the exclusiveness not only in the DDR3 1333 MHz, but also in the support of 2 ports NCV Express train 2.0 16X. A standard which allows the doubling of the band-widths as well as power transmitted to the graphic ports (150 W against 75 W currently).


2. P35: new controller report and others

Substitute of the chipset with success P965, P35 thus supports officially the FSB 1333 MHz as well as the DDR3 up to 1066 MHz, although only certain models of mother boards will be available for the sites necessary. The DDR3 functions according to the same principle as the DDR2, namely to divide once again by two the internal frequency of the chips but to double in parallel the quantity of data transmitted by cycle (it is said that the prefetch passes to 8 bits), to reach the beach of frequency of 800 - 1600 MHz, against 400 - 800 MHz for the DDR2. Official beach certified by the JEDEC of course, since in practice the most aggressive manufacturers exceed the 1200 MHz with the DDR2.

The largest interest of the DDR3 will initially remain its consumption reduced, obtained in particular via the reduction of the supply voltage (1,5 V instead of 1,8 V for the DDR2, which results from the passage to the 0.09µ). The escapes of current are in addition limited via the use of the transistors to 2 grids. With final the profit in consumption the 25% between the DDR3 and the DDR2 would exceed on modules 800 MHz, and the DDR3 1333 MHz would not consume more than the DDR2 800 MHz.

Because of an external frequency more raised, other optimizations are used as a direct connection of each chip memory between them via the adress buses and of control, instead of a topology in T. Lastly, an interesting functionality lies in the addition (optional) of a temperature sensor which used well could also make it possible to save energy within the framework of the portables (but not before the next year thus), and incidentally to check the utility of the radiators of bars.

Remain that the agreement of the prices of the DDR3 with those of the DDR2 was shoed only some share in 2008, and that while waiting for this memory will remain in 2007 very expensive and thus of a worse performances ratio/price than the DDR2.

The controller report was thus improved, but not only via the support of the DDR3: technology Fast Memory Access was added. Enough near in the principle with the NCQ, it makes it possible to reduce the latencies caused by the chipset and to maximize the use of the band-width memory. Its principle of operation consists in analyzing the queue of the requests of reading in memory, in order to determine those which want to reach the same pages. They will then be gathered independently owing to the fact that they were subjected to different moments and that other requests were intercalated between them. With final, the new controller will have finished his queue before the precedent, and less preloadings and activations of the pages will have been necessary.

It is not all: the unutilised cycles are also identified in order to benefit from it to run out the queue concerning the requests of writing this time.

It should be noted that this reorganization does not relate to only the requests placed on the FSB, but also those of the integrated graphic circuit, peripherals NCV Express train and the DMI (Direct Media Interfaces).

This functionality should allow a large profit in performances compared to current P965, including with simple DDR2.

To finish side northbridge, P35 introduces simply the possibility of managing memory DDR2 1066 MHz and either 800 MHz. On the other hand, the possibility of completely desynchronizing (including downwards) the frequency of the RAM and the FSB, following the example i975 and nForce 6 thus, will be reserved for X38. What however simplifies the overclockings and makes it possible to save on the level of the bars memories.

[Jeffrey]

3. ICH9: Matrix, Turbo Memory

Side southbridge the ICH9 makes its appearance. Let us start with what this chipset brings obligatorily, namely the support of 4 ports S-ATA, the absence of any port P-ATA (additional controllers to envisage for the board manufacturers mothers), and the management of the eSATA. It acts for recall of this port located on the back plate of the mother board and aiming at replacing the USB and FireWire for the management of the external hard disks in particular. That managed by the ICH9R supports the multiplication of port, which wants to say that it will be possible to connect to 4 discs with this only port via a simple external case with the nappage thus pointing out the IDE.

Side of the optional functionalities, Turbo Memory makes its appearance on the mother boards for PC! One of its advantages sees strongly reduced blow, since the fall of consumption which it can generates via a less request of the hard disk becomes negligible on a PC scale. In the same way, the PC generally lay out of more than read-write memory than the portables, which should reduce the interest of this memory flash. Blow, instead of kits 512 Mb or 1 Gb one passes to the choice to 1 Gb or 4 Gb. The interface is always port NCV Express train X1 (250 bidirectional Mb/s). This memory will be sold by Intel directly to the manufacturers (as for the portables), which authorizes the possibilities of upgrade via the development of an optional module suggested by the manufacturer, which appears however not very probable. On the other hand, some will propose mother boards with this welded memory. The prices were however not revealed and will be to it only on June 4. By hoping that the stable and powerful drivers will be quickly available, under penalty of seeing this technology trailing a bad image definitively.

Technology Quiet System makes its appearance. It deals with the management the speed of variation of the ventilator processor according to the temperature, obviously with an aim of avoiding the traditional thermoregulation which has as a disadvantage of accelerating the number of revolutions and thus the noise with the least request of the processor, which is unpleasant. It would thus exploit the margin available to the processor before reaching the limit requiring a fall of its frequency and its tension in order to remain longer at a number of weak revolutions, although in the case of a constant use continuously, this technology cannot obviously stop the increase speed. A debatable technology thus insofar as it does not change anything with the need a quiet ventilator for those which are sensitive to the noise, the more so as of many manufacturers of mother boards have identical technologies already.

3 versions different from the ICH9 are available. The ICH9DH is that reserved for the Center Media with the support of the Viiv (from where the presence of Matrix Storage, which does not manage the RAID but the AHCI, essential to the Viiv). Attention, it is also the first to integrate 6 ports S-ATA, the initial version integrating some always only 4.

Lastly, the version R is like always most complete, the only one to manage Matrix Raid, Turbo Memory and the multiplication of ports.


4. G33 and manufacture

G33, successor of the 945G and not of G965, introduced into the world of the PC the graphic circuit GMA X3100 which we saw at the time of the article on Centrino 4. Not what to thus jump to the ceiling, but at least to bring the support of an essential exit HDMI HDCP from now on for a PC Center Media, and incidentally the material assumption of responsibility of the vertexes shaders.

Manufacture and TDP

Always using a smoothness of engraving of 0.09µ and wafers of 300 mm, P35 and G33 would also divide a number of transistors of 45 million for the northbridge, which is however not possible considering the absence of the graphic circuit and any additional element in P35, and of 4,6 million for the ICH9. The proper documents of Intel are also contradicted on the level of maximum dissipation thermal, although it seems to be of 16 W for P35 and 14,5 W for G33, that is to say in fall compared to 19 W of P965 what is a good news. On the one hand because that means a lowering of the total consumption of the PC, which is from now on the business of all the components, and on the other hand because such values make it possible to do without ventirads, but also radiators containing heatpipe to the design left the most insane dreams of certain designers, in spite of what some manufacturers try to do to us to believe with their models…

5. Assessment

With final, more than the support of the DDR3 which should remain rather in 2007 fault of a real sensitivity of Core 2 Duo with the frequency memory (especially beyond 800 MHz and in spite of the arrival of the FSB 1333 MHz) and of acceptable prices, P35 and G33 should especially surprise by the performances of their controller report compared with that of P965. Remain that there still, that will not be a pretext sufficient with a board swapping mother for those already equipped with a P965 model considering the effectiveness of the schedulers of Core 2 Duo and the price of a mother board medium/top-of-the-range current. What to in any case maintain the pressure on nVidia, whose chipsets very effective Intel always pain to bore. The arrival of Turbo Memory is interesting but it remains to check its effectiveness and especially its overcost compared to the standard models, which should constitute the key of its adoption (in particular for the model 4 Gb).

Remain that most attentive will have noticed that the most interesting chipset of this new range will be unfortunately available only with the second wave of this launching, that is to say in the third quarter. Damage, because X38 is announced clearly like perennial with its support of the NCV Express train 2.0 which would have charmed those which do not like to have to change their mother board every year, one of the weak points to the Intel platform since the end of chipset BX.

[Killen]

Can it be used as Dx 10 graphic chipset?