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- Date:
- Monday , April 04, 2005
- Author:
- Kyle Bennett
- Google +1
Pentium Dual Core Preview
A preview of the Intel Pentium Processor Extreme Edition 840. We give you some thoughts, impressions, and feedback on working with Intel's first dual core processor and what it brings to the table.
Introduction
We have only been afforded a few days in which to present this to you, so please do understand that there will be following articles that will cover Intel’s dual core processors with hopefully much more usable information. Today is not a launch date for Intel, but rather a preview of upcoming technology. The rumored launch date is May 15, but that is not confirmed. That said, our objective here today is to give you most of the needed facts to help you understand just what Intel dual core processor technology is really “all about.”
The 840 Processor
The processor we have in hand today is the “Intel Pentium Processor Extreme Edition 840.” You will see it carrying the logo below.
The Intel 840 processor packaging is staying familiar in that we are seeing the LGA 775 format that we have come to know.
And even the core of the CPU is very much unchanged in a sense. Inside you will find what is codenamed the Smithfield core. The Smithfield core consists of what is best thought of as two of the current Prescott processor cores linked together on an 800MHz Front Side Bus.
Clicking on the core pictured above will take you to a 300KB JPEG of the Smithfield core. Scrolling up and down you can compare the two halves of the Smithfield core for yourself. You will see that they are very much mirror images of each other.
Our Smithfield core, as you would expect houses 1MB of L2 cache for each on-die processor.
Our Intel 840 will have an operating voltage between 1.2V and 1.4V and have a Thermal Power Design of 130W. To put it succinctly, these 840 processors will be hot, just like the Prescott Pentium 4 cores we have seen lately. That said, considering we are putting two Prescott cores in under one heat spreader, the thermal impact has not been nearly as high has we would have thought.
The Intel 840 is still capable of air cooling and the factory heatsink we are using is very similar to what we have seen in the recent past.
The capabilities of our Intel 840 are like no other desktop processor that has ever been seen. The upcoming mainstream processor from Intel will be the “Intel Pentium 4 D” and it too will be a Smithfield core CPU. The difference between the “D” and the Extreme Edition Smithfields, other than model numbers and core speeds, is the fact that the Intel Pentium Processor Extreme Edition processors have HyperThreading activated. This will give the new Extreme Edition processors the power of two physical processors and two virtual processors. And as “luck” would have it, this is exactly what the capability of a Windows XP Professional operating system is. Please note that not all operating systems are capable of supporting an Extreme Edition 840.
In the screenshot above you can see the four panes under “CPU Usage History.” Each of these windows represents a thread available on our Intel 840 processor. Two of these windows represent one each of the two physical cores on our Intel 840, and two of the windows represent two virtual processors supported by Intel’s HyperThreading.
Below is a CPU-Z screenshot that outlines the processor specifics.
You can see where we have extended the menu drop box for CPU selection that shows both two physical processors and two virtual processors that you can ID. The “logical unit” identifies the activated HyperThreading. All physical and virtual processors show the same information.
Interestingly enough, our core clock speed is not near as high, a full 600MHz slower, as what we will find on 3.8GHz Pentium 4 processors that are for sale today. It is our opinion that Intel is currently seeing thermal limitations by utilizing Smithfield cores that are any faster.
Also worth noting is the addition 64-bit instruction code, as noted by the “x86-64” in the Instructions line. Intel’s official nomenclature for this is “Intel Extended Memory 64 Technology,” or “EM64T.” To utilize a 64-bit CPU, you will of course need the proper operating system. Windows XP Pro 64 Bit Edition is due out this year.
The Intel 955X Motherboard Chipset
While this Intel 840 looks the same as current Pentium 4 processors, you do need to know that Intel’s dual core processors will require the new Intel 955X motherboard chipset for operation. This is much in contrast to AMD’s upcoming dual core processor that will require little more than a BIOS update to operate on current 939-pin motherboards.
Below we see the sample Intel Desktop motherboard we have used for testing, the D955XBKLKR, codenamed “Black Creek.”
Some of you will notice two X16 PCIe slots and some of you might even notice the absence of a CMOS chip. This initially gave rise to use searching through our boxes for the loose CMOS with the needed BIOS. We were soon educated that we did not need our lost CMOS chip with this new 955X chipset. The 955X has a new technology called SPI. This allows the storage of the BIOS code on a chip with other devices such as a LAN chipset. Currently on this board it is not shared but housed on a small 8-pin SPI chip between the PCI slots and the ICH7R southbridge. Can you find it?
This motherboard will come in both ATX and BTX form factors. The 955X chipset will allow for Extreme Edition and Pentium 4 D dual core support, both 1066 and 800 MHz system bus, with new DDR2-667 and DDR2-533 support.
Below are more CPUZ screenshots, these outlining motherboard and 667MHz memory bus specifics.
The third shot is probably one of the most interesting as it shows just how the SPD on the memory scales the timings as frequency increases. If you are interested of the impacts of latency as our new DDR2 speeds up, Corsair has produced a PDF that visits these exact issues.