Power Consumption and Deciphering the Results

Power Consumption

All that extra processoring horsepower doesn’t come free, of course, as we’ll see here in our power consumption test results.  Using a Seasonic Power Angel reader that reads power consumption at the wall plug, I got the “idle” power consumption numbers from the Windows Desktop and the “load” from a run of CineBench 2003’s rendering test.

Intel Pentium Extreme Edition 840 Processor Review - Processors 66

As you can see here, the Pentium Extreme Edition 840 eats up a LOT of power.  At idle, it uses 25 watts more than the 3.73 GHz XE processor based on a single core die.  In fact, the Athlon 64 4000+ system uses only 7 watts more power under a full load.  Speaking of load, did you see that the XE 840 almost hits the 300 watts level under one?  That is with only one X800 XT GPU too!  Obviosly, a high quality power supply is required for this kind of setup. 


Ah yes, where to start?  The performance of the new Intel dual core processors, in particular the Pentium Extreme Edition 840 we tested here, is starting a problem where performance is difficult to judge and measure.  For most single threaded, single tasking benchmarks and applications, the XE 840 isn’t going to be in the top five of processor performance.  The Athlon 64 high end processors and the Pentium 4 XE processors and 600 series processors that are clocked faster than the 3.2 GHz of the XE 840 are going to walk on top of it.  It just makes sense — if the extra core isn’t being utilized much, if at all, a 3.73 GHz Prescott is obviously faster than a 3.2 GHz Prescott.  And anywhere you saw the Athlon 64 out perform a single core Prescott at 3.2 GHz, you can expect to see that same Athlon 64 out perform the XE 840 too!  Of course, this dependent on the single threaded, single tasking scenarios.

If your applications are heavily multithreaded, such as most high end 3D rendering applications like 3D Studio, CineBench or KribiBench, then the added benefits of dual core and HyperThreading are going to probably boost performance of the Pentium line up over that of the Athlon 64.  With the Pentium XE 840 having BOTH dual cores and HyperThreading on each core, it also makes sense that even at a slower clock speed, it will probably out pace the faster P4 processors with only HyperThreading. 

Intel Pentium Extreme Edition 840 Processor Review - Processors 67

In multitasking it gets a lot more complicated.  Multiple applications run at the same time, either in the background or foreground, take up CPU cycles.  With a dual core processor, you have theoretically twice as many cycles to use than the clock speed indicates.  Assuming you are using an OS that can handle multiple threads and processors (like Windows XP Pro) then having more applications open and working will have less of an affect on your overall system performance with a dual core processor compared to a single core processor.  This is a lot more complicated than just operating systems if you include the complexities of different CPU architectures between AMD and Intel, different memory controllers and different clock speeds and IPCs.  There really is no clear cut mathematical formula for finding the fastest, optimal processor solution.  Otherwise, why would you need me?

That all being said, in our multitasking tests I’ve found that the Pentium Extreme Edition 840 outperforms any other processor in a highly multitasked work environment.  With seven or eight applications open in our first scenario, the Intel XE 840 was clearly the best performer under those circumstances, and I would wager a bet that adding more and more applications to that setup would only further Intel’s lead. 

In our light multitasking scenario, the AMD platform came out on top, though its lead in the benchmark was diminshed due to the other applications running in the background.  This leads us to the assumption that for those users in a light or no multitasking environment, choosing their processor based on the best performance for the users primary applications still makes the most sense. 

Finally, in our gaming tests, we saw that only having a small background task scenario running didn’t affect the scores as much as we thought they might, and the Athlon 64 FX-55 processor still came out on top.  Adding more and more programs to the background would surely tilt the results in the other direction, but we haven’t yet found that peak yet.  Further testing here at PC Perspective will surely come across it.


While there aren’t any really new features on the processor, the 955X does offer an upgraded memory controller for 8 GB of system memory and support for DDR2-667 speeds. 


I would expect to find the pricing of the new Pentium Extreme Edition 840 processor to fall right at $1000 per unit.  Couple that with the cost of a new motherboard based on the 955X chipset, and some memory, and don’t be surprised if the cheapest you can get this new setup for is about $1500-1800.  That is not a small chunk of change. A cheaper Pentium D dual core processor is also going to be available soon, but I didn’t get one here to test so we’ll save discussions of that CPU until we have it. 


We already mentioned that the 925XE and any previous Intel chipsets for the LGA775 socket would not support the new dual core processors.  But what about the recently released NF4 Intel Edition chipset from NVIDIA

A talk with the folks at NVIDIA revealed that though the chipset does support dual core processors, its up to the individual motherboard manufacturers to implement the corrent support for them on their product.  I guess that means you’ll have to keep checking back here at PC Perspective for the latest motherboard reviews that test that compatibility.

Final Thoughts

This is really only step one of a much larger war about to hit all of the PC enthusiast community head on.  AMD’s dual core processors are going to be released in their Opteron form tomorrow, and though I didn’t get one for a review, I know some reviewers who have so look for comparisons to be around.  AMD is still indicating that their desktop dual core parts are still going to be available in the June time frame, though I don’t see why they wouldn’t push things up a bit to add more heat on Intel.

Gamers may still question Intel’s ability to market the XE line as the “gamer’s option” especially now that we are back to running at 3.2 GHz and multithreaded games are nowhere to be found.  AMD’s decision to keep their FX line as a single core product makes more sense for gamers that really only focus on gaming, but Intel may be able to capture more of the gaming market if hardcore gamers also find themselves being the hardcore multitaskers outside of the game world.

The Intel Pentium Extreme Edition 840 processor is an outstanding performer when looked at in the proper light.  That light happens to be in heavy multitasking environments, where the available four threads of execution have lots of room to shine. 

I welcome all comments, ideas and suggestions for future dual core reviews — all feed back is welcome!

Be sure to use our price checking engine to find the best prices on the Pentium 4 3.73 GHz Extreme Edition, and anything else you may want to buy!

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