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A 4.1 GHz Dual Core at $130?
joshmo97 writes "Tom's Hardware has found that the Pentium D 805 runs stable at 4.1 GHz and outperforms Intel and AMD's flagship offerings in many benchmarks. From the article: 'The Pentium D 805 is a budget CPU, but it puts lots of processors from AMD and Intel to shame. Although it is not based on the latest 65 nm core, this CPU remains stable even when operating at amazing 4.1 GHz. The Pentium D 805 ascends to the throne as the new King of overclocking, knocking out the AMD Opteron 144.'"
Ok, so you can overclock it to 4.1Ghz.. but how many weeks will it last before it burns out and you need to buy a new one?
The theory of relativity doesn't work right in Arkansas.
With minimal alterations, you can also perform mad overclocks on your articles!
They watercooled this 10 page story up to an incredible FORTY FIVE pages, using only duct tape, a small iceberg and tons of adverts. Wow!
SET YOUR CLICKING FINGERS TO STUN, LADIES!
Instead of Athlon64+ 3200 and X2 3800s, we built a few machines at the office with P-D 805s. Every user has complained about how hot it gets under their desk with the machines. You reach down and put your arm under the desk, and it's like a sauna. We haven't had any complaints with the AMDs.
Oh, you're not stuck, you're just unable to let go of the onion rings.
This processor, when overclocked to 4.1 Ghz, draws 260 Watts.
That will run up the electric bill just a little.
Too bad that "free" 1.5GHz comes with a 216W increase in power consumption, totalling nearly 500W for the system.
The best thing about the 805 is that the motherboards are so cheap as well! There are definitely bigger and better CPU to lust after, even in terms of price/performance. But then, picking a decent motherboard for say a Dothan or Core Duo that is stable usually takes you to the enthusiast territory and the total system ends up costing much more than you intended. Athlon is an exception, of course. However, overclocking a 805 is like buying a dirt cheap supercompact or hatch, modding the engine, and getting a kick out of everytime your 10k car stays neck to neck with 50k sporty cars :-D
Sorry for adding to the cesspool of odious car similies!
[Note: this is the first 10 pages of the article, with images removed. The charts are given as tab-delimted text.]
There are still some situations in life that are guaranteed to put a grin on anyone's face, even hard-boiled technical skeptics like us. This particular story borders on being a sensation unmatched in our last eight years of hardware reviews. The news, for those who just can't stand the wait any more, is this: Intel has offered a budget Pentium as part of its processor line-up for a little while now. With a simple modification, however, this CPU can outperform every top-of-the-line processor around.
The bottom line is that the Athlon FX-60 and the Pentium Extreme Edition 965 have both met their match - there's simply no escaping this conclusion! This is bound to cause lamentation among the elite circle of users who've invested big bucks in their high-end systems, if not outright wailing and rending of garments. The basic stats for this insignificant-seeming budget processor read as follows: Pentium D 805 clocked at 2.66 GHz, equipped with two processor cores both with 64 bit support. At your friendly neighborhood retailer you can pick up this secret weapon for pocket change - right now, for example, it's available at newegg.com for just under $130. We were quite amazed as the first performance figures emerged from our test labs: stable operation was possible at 4.1 GHz, and without even the need for substantial boosts to cooling!
As one of our more enthusiastic readers wrote to us a few years ago, when we were chasing new overclocking records on what seemed like a daily basis: "I'll knock your numbers down to the ground." In this case, he was referring to the video encoding performance numbers that a heavily overclocked system could post when compared to a stock PC. We've also seen another similar phenomena in days of yore, which ambitious (but older) users probably remember. For example, the Intel Celeron 300A, for which a 300 MHz clock rate was specified, worked flawlessly at 450 MHz. Foreshadowing our current champ, this low-cost offering also knocked a much more expensive Pentium II 400 into the back seat.
The Pentium D 805 gives Intel an unassuming budget CPU for its processor portfolio, but simply overclocking the device to 4.1 GHz puts it ahead of top-of-the-line high-dollar processors. For overclocking aficionados this means one thing: the AMD Opteron 144, which led the overclocking pack until just recently, has been dethroned by the Pentium D 805. This latter processor is not only easier on the pocketbook, it's also a noticeably better performer, thanks to its dual core architecture - the Opteron offers only a single core.
The Pentium D 805 is based on the first Intel dual core processor, the Pentium D with the Smithfield core. Its predecessors in this family were rated at clock speeds of 2.8 GHz (D 820) to 3.2 GHz (D 840). Both cores in this CPU family come equipped with a 1 MB L2 cache, whereas the most current dual core processors in the 900 series make 2 MB available to each core. For the last year, Intel has brought no new models in the 800 series to market, because the company has switched its fabrication from a 90 nm process to a 65 nm one in the meantime, and has used this smaller building block size only for processors in the 900 series. But then out of nowhere, the old Smithfield core put in another appearance in the form of the Pentium D 805.
By comparison with all the other processors in this series, the D 805's relatively low clock speed of 2.66 GHz doesn't make much of an impression on store shelves. At 133 MHz (533 QDR), its front side bus clock rate is laughable when compared to state-of-the-art CPUs with 200 and 266 MHz speeds.
The Secret Of The Multiplier
The multiplier expresses the ratio between the processor clock speed and the FSB clock. For the Pentium D 805, the combination of FSB and processor clocks results in a multiplier value of 20x. By comparison with other CPUs with 200 MHz or 266 MHz FSB, this is a very high valu
Honestly I've been there and done that, I think I still have my Celeron 300mhz running at 450mhz somewhere around here. But these days, all I really want in a computer is something that has decent performance and doesn't sound like a vacuum cleaner. I'd much prefer to know which CPU's I can undervolt/underclock, and reduce the DB to a minimum.
If you had RTFA you'd see that overclocking this card to 4.1 isn't actually a big strectch because of the unique way this chip was designed by Intel.
Normally the clock multiplier is in the 10's but on this chip it is 20x. That means that a relatively small change to the FSB clock increases the overall clock speed greatly.
The default FSB speed is 133mhz. 20x133 = 2.66ghz (the original speeds)
By raising the FSB by only a bout 70 mhz to 200 we get a huge change. 20x205= 4.1ghz
It's a relativley low increase in FSB speeds that translate to a much higher clockrate.
The article seems to claim that one chip could be overclocked to 4.1GHz. That's a far cry from saying that all such chips will work at that clock speed. A sample size of one isn't very informative about a population.
I thought you were kidding about the 45 pages til lI checked the article. I am not going to sift through all that, I'll wait for Anandtech to cover it.
Saying Java is nice because it works on all OS's is like saying that anal sex is nice because it works on all genders.
I have my IBM PC XT overclocked to 5 GHz, unfortunately it costs 50 KiloWatts to run, but on the plus side I can use it in my kiln to cure pottery.
stuff |
US military to Intel "your latest shipment of Mil-Spec CPU's are not up to standard"
Intel to US military "That's strange, we sent you our very best core's"
Somewhere at Intel after reading Slashdot " $@&#$%&!!!, is that where they went"
It's been known for a while that AMD's Opteron 165's ($330) will o/c to at or above the performance of an FX-60 ($1000).
All this article really says is that the ultra-high-end isn't worth it.
I'd like to see a comparison between this thing and the Opty-165 o/c. The Pentium may be a bit cheaper, but factor in the power and cooling bill and (I expect) the higher performance of the Opteron, and it's probably about even.
I notice that while the clock rates climb quickly, the performance levels on most real world benchmarks level out pretty quickly. So why bother waste all the time and electricity?
And a hefty power bill to go along with it.
I picked up a 805 myself and just like Tom's I could do 3.33 with stock vcore. Read any other ocing articles on the 805 and 4ghz can only be achieved with water cooling. Even if you shoot for 3.8 you are going to need a $60 heatsink and pray it gets the job done.
He also says: "It's noteworthy that the core voltage levels of 2.7 volts didn't read out correctly here."
This isn't true according to my testing. CPUZ shows the correct voltage, well close to it anyways. For some reason currently shipping intel motherboards and nf4 intel motherboards have a hard time supplying the correct voltage when oced and under load. The voltage always drops by a substantial amount, for example at 3.33 it drops from 1.337 to 1.25 while under load. I broke out my multimeter to make sure since I was contemplating upping the voltage in the bios to compensate.
At any rate I would say ocing it to 3.33 is good enough considering the price.
Oh and why fsck did this article need 45 pages?
The original clockspeed was 2.66GHz. Just thought I'd highlight that fact since it was nonsensically omitted from the summary and I haven't seen anyone else mentioning it.
I mean, c'mon, how many people know what the original speed of the conveniently named Pentium D 805 is off the top of their heads anyway?
1) Using the Standard Intel CPU cooler the processor wasn't even stable at 3.3Ghz, so they put on a zalman cooler.
2) The zalman cooler wasn't good enough and would throttle after 3.8Ghz
3) The 4.1Ghz was achieved using water cooling. The CPU is rated at 1.4v max and they had to run it at 1.56v to make this work.
The headline says "A 4.1 GHz Dual Core at $130?" - but you'll need water cooling to make it to 4.1 ghz and that will at least double the price. Not to mention you'de probably need a new power supply.