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  • wavetrex - Friday, May 28, 2010 - link

    In the table it sais $284 for the 980X, that MUST be a mistake! Reply
  • mianmian - Friday, May 28, 2010 - link

    In a previous Anandtech aritical, it was $999, maybe it is $824 now Reply
  • Texpat - Friday, May 28, 2010 - link

    I think the price for the 980x might be wrong. $1,000 would be closer tot he truth. Reply
  • ltcommanderdata - Friday, May 28, 2010 - link

    I'm really pleasantly surprised that the 2.93GHz Core i7 875K at $342 is cheaper yet has more features than the 2.93GHz Core i7 870 at $562. Although I'm guessing that's only temporary as the upcoming 3.06GHz Core i7 880 will probably take over the $562 price point, with the Core i7 870 dropping down to $284 and the Core i7 860 being phased out. There's also a Core i5 760 to replace the Core i5 750. Reply
  • DrMrLordX - Friday, May 28, 2010 - link

    You guys really busted out the big guns with the dual-stage cascade! Please do this more often when overclocking. I would love to see a C3 Propus at -100C (or a Thuban). Reply
  • jleach1 - Friday, May 28, 2010 - link

    On the second page, i believe in the 'test rig' table the proc is listed as a i5-870 instead of the i7-870 Reply
  • Rajinder Gill - Friday, May 28, 2010 - link

    Thanks - fixed! Reply
  • GeorgeH - Friday, May 28, 2010 - link

    "it’s full of talk about voltages and harps on about overclocking"

    No need to be shy about that - Anandtech is bookmarked because of awesome articles and analyses like this one.
    Reply
  • FlanK3r - Friday, May 28, 2010 - link

    not bad, my x6 1090T is full stable 4300MHz 2800MHz NB with aircooling ,-)...for games and benchmarks 4400-4450 MHz :) Reply
  • AstroGuardian - Friday, May 28, 2010 - link

    Guys, i think you should not hurry to release articles instead of taking them slow and sure. Many typos especially in the graphs.

    i3-530 vs i5-540
    Reply
  • Ph0b0s - Friday, May 28, 2010 - link

    Not covered so much on these websites but I slurged on an I7 965 when I7's were new, becuase it was unlocked, even though I knew it did not have any extra head room than the cheap chips in the family. The reason I did this was so that I could use the I7's new turbo feature to overclock on demand instead of having to use static timings to overclock. With unlocked I7's and the right motherboard you can change the value of the turbo mulipliers to be more than just one or two steps.

    So for my chip if I have all 4 cores in use my turbo muliplier is set to x29 (3800 ghz, only using factory voltages at the moment) and higher amounts when less cores are in use. So when not doing anything my CPU clocks itself to 1.6 GHz and runs at 3.2 GHz if not doing too much and then clocks itself to 3.8GHz when extra power is needed.

    So I really welcome Intel putting out these cheaper unlocked CPU's, as next time when I want to overclock using the turbo funtionality I won't have to fork out for an Extreme Edition again.

    Also I would love to see more coverage of this type of overclocking that it is new with the Nathelems, Before it was only the I7 Extreme Edition chips that could do it, but now that are more options avaliable, maybe Anandtech could do an article taking about it.
    Reply
  • Death666Angel - Friday, May 28, 2010 - link

    Hello guys!
    I was really looking forward to Intel -K material. But the whole bunch of "i5 540" is more than an annoyance. It is downright embarrassing and I would urge you to re-read any future texts, as I am really not interested in reading stuff when so little time is put into the text. Really a shame since the content is looking good.
    Reply
  • Rajinder Gill - Friday, May 28, 2010 - link

    Sorry, blame me for that. Those skipped under the radar this morning.

    -Raja
    Reply
  • Griswold - Friday, May 28, 2010 - link

    If you wonder why Intel does this, it most likely boils down to two letters: BE. They were never priced as if they came straight out of Absurdistan. And perhaps Intel felt a little itch because of that... Reply
  • Maroon - Friday, May 28, 2010 - link

    ^^^we have a winner! Reply
  • DanNeely - Friday, May 28, 2010 - link

    Where are you getting those numbers from? Software or are you using hardware to measure it directly off the mobo itself? Reply
  • Rajinder Gill - Friday, May 28, 2010 - link

    Hardware measured using a clamp meter.

    Raja
    Reply
  • DanNeely - Sunday, May 30, 2010 - link

    So you were measuring the current going into the mobo via the 4/8pin 12V cpu power cable? Reply
  • Rajinder Gill - Monday, May 31, 2010 - link

    Yes. Reply
  • DanNeely - Tuesday, June 01, 2010 - link

    Did you also monitor the main ATX power connector to see if there was any increase in power draw there when overclocking? Reply
  • Rajinder Gill - Tuesday, June 01, 2010 - link

    As the graphs state - this is VCC/VTT power only, the two major power rails of this architecture. The 12V ATX fan headers and PCIe 12V only on the E659 motherboard. Power to DDR3 is not something I focused on but may do in a future piece (there will be a frequency proportional rise in power provided timings are not changed). A very crude guess - I'd expect the rise over stock to be around 5 watts on the DRAM side in this frequency band (and total draw to be no more than 10~15w). Although figures would differ according to the scaling capabilities of various modules.

    Other than that, there's not much else aside from CPU PLL which is specified at around 1.1 amps at 1.8V (around 2-3 watts tops).
    Reply
  • Rajinder Gill - Tuesday, June 01, 2010 - link

    EDIT: The 12V ATX fan headers and PCIe 12V only on the E659 motherboard.

    That should read the 12V ATX line supplies fan headers and PCIe 12V power only. The 3.3v and 5V rails supply DDR, CPU PLL, IOH (and all derivatives such as IOH PLL, SB~IOH termination voltage etc).

    Later
    Raja
    Reply
  • DanNeely - Tuesday, June 01, 2010 - link

    Time permitting I'd be interested in seeing those numbers as well. I understand your desire to measure power consumption closer to the source. My concern is that increased power consumption from the secondary items you're not measuring is a black box; while the AC-DC conversion loss in the PSU from measuring power at the wall can be mostly corrected away by looking at what the efficiency rating of the PSU used in the test setup is. Reply
  • DanNeely - Tuesday, June 01, 2010 - link

    Time permitting I'd be interested in seeing those numbers as well. I understand your desire to measure power consumption closer to the source. My concern is that increased power consumption from the secondary items you're not measuring is a black box; while the AC-DC conversion loss in the PSU from measuring power at the wall can be mostly corrected away by looking at what the efficiency rating of the PSU used in the test setup is. Reply
  • Rajinder Gill - Tuesday, June 01, 2010 - link

    I prefer to keep things at the DC level. There are plenty of articles covering wall level consumption with your standard kill-a-watt type unit (and they also state the PSU used so users can factor out the losses if they know the effective efficiency curve). I think you are worrying too much about the lesser rails. Sure they will make interesting reading at some point - but there is nothing that pulls more than a couple of amps so the effects on power consumption will not be huge.

    Regards
    Raja
    Reply
  • Rajinder Gill - Tuesday, June 01, 2010 - link

    Ok "DanNeely", this is for you,

    I just ran tests on the 3.3V and 5V rails. At stock the combined power consumption of these two rails on the E659. Bear in mind this is an enthusiast level board (higher switching losses due to higher switching speeds on VDIMM, plus using an NF200 for PEG multiplexing):

    Running DDR3-1333 CAS 8-8-8-24 with 4GB of memory. (3.3v + 5V rails combined).

    20.2 watts idle
    Linpack load = 26.36 Watts.

    That's a change of 6 Watts between idle and load.

    At 4.551GHz, now running DDR3-1820 (1.60 VDIMM):

    Idle = 22.86 Watts (2 Watt idle increase)
    Load = 27.86 Watts.

    That's a 1 Watt increase over stock speeds under load with an overclock of 1GHz on the CPU (running QPI over 4GHz). Hardly worth writing about. Do note - the effective change will vary from board to board according to VRM switching efficiency (which is coming into play if you look at the deltas between idle and load). Of course, I am not including things like HDD's etc although, some of the static 3.3V and 5V rail consumption is due to the GPU (GTX 275) which also draws a little power from that rail.

    Hope that answers your questions.

    Regards
    Raja
    Reply
  • DanNeely - Tuesday, June 01, 2010 - link

    yes it did. thank you. Reply
  • tno - Friday, May 28, 2010 - link

    Setting aside typos, I know wall of text is to be avoided but this felt almost like the opposite problem. Additional clicks for additional adviews. Clearly you didn't like what you saw out of the chips despite the voltage improvements evident in the more modest chip. Yet in the end despite devoting 1/9th of the coverage to it, you reward your recommendation to the pricier chip just one page after showing it severely underperforming its non-K analogue in both overclocking and voltage.

    I have said it before and I think its worth mentioning again, clearly there is a lo of passion for tech in the growing AnandTech team, but maybe adding a team member whose passion is writing and across whose hands every article will pass would give the site that extra polish that elevates it from other tech sites.

    Jason
    Reply
  • 7Enigma - Friday, May 28, 2010 - link

    At first I thought the same thing (saying nothing at all in the final page about the 655K does leave me puzzled as it is good), but Rijinder did clarify his recommendation for the 875K by saying PRICE. He is saying for the price of these chips and where they fall in line with the rest of the offerings from AMD and INTEL, the 875K is in a sweet spot. Remember the 655K is a dual-core,4 thread chip for $215 (lots of competition from both camps), while the 875K is a quad-core, 8 thread chip for under $350.

    In the end (and after re-reading the conclusion and article) I think the last page needs to have a bit more meat behind it. The data in the article itself is very detailed, but the final wrap-up needs some work. But honestly, since it's a free site, I'll take the good data and sketchy conclusions (I tend to make my own).

    Thanks for the article!
    Reply
  • troun - Friday, May 28, 2010 - link


    "Past 3.9GHz, we’re already looking at a 10W increase in power consumption for every 20 MHz rise in CPU frequency"

    But I read 20W for 100Mhz (or 10W for 50Mhz), with ~160W @ 3.9Ghz and ~180W @ 4Ghz...

    However very interesting article, a similar curve (W/Mhz) would be also appreciate for an i7 9x0 comparison, 32nm Vs 45nm (980 Vs 930?).
    Reply
  • Rajinder Gill - Friday, May 28, 2010 - link

    Hi,

    The actual "break point" is at 3.962GHz to be precise. A 9W step to 3.986GHz, followed by a 11w step to 4.009GHz. Anything higher than this and I'm loading up at 85C (according to DTS) and I can't get Linpack stable. I've extended x to show the 4.009GHz point. We'll endeavour to plot some more curves featuring some of the parts you mention if time allows.

    Thanks!
    Raja
    Reply
  • Spenny2112 - Friday, May 28, 2010 - link

    This only further confirms the change that the pc industry will be undergoing in the near future. Reply
  • Interitus - Friday, May 28, 2010 - link

    Why does this make any sense on the 1156 platform? Intel created 2 different platforms, 1366 enthusiast and 1156 mainstream. Why is this on 1156 and not on 1366? Does that make any sense since 1366 is supposed to be the enthusiast/OC/hardcore version?

    Keep in mind I'm not arguing the viability of either socket. I'm just saying that Intel designed 1366 to be the high end, so why do this for the low end, but keep the unlocked chips for 1366 at $1k?
    Reply
  • blandead - Friday, May 28, 2010 - link

    1 reason that comes to mind first... $$$$$$
    2 this isn't targeted toward the enthusiast overclocker

    the ones buying 1366 don't need unlocked multipliers to reach 4ghz or 1800+mhz ram speed.

    I'm an AMD fanboy and my friend bought an i7 930 and 2000mhz ram and asked me to overclock it. I've never played with an i7 before, but surprisingly it was easy as cake to get it to 4.1ghz and 1850mhz ram on air and still have QPI overclocked past 6.4 dont quite remember i dont use the i7. Point is, with those achievements on a 930 I don't see a need for unlocked multiplier or k series.
    Reply
  • TheBLK - Friday, May 28, 2010 - link

    So why the messing BLK ???? Reply
  • geokilla - Friday, May 28, 2010 - link

    That's a huge jump in power consumption... But then these are engineering samples. I hope the retail ones will be better. Reply
  • Jamahl - Friday, May 28, 2010 - link

    "This is another of those situations where we’ve had to make an eleventh-hour conference call with Intel to work out what and who these processors are aimed at."

    How about you make your own minds up instead?

    First Anand did it with the awful clarkdale now you are doing it with these similarly awful cpu's. If intel gives you shit, TELL US ITS SHIT. Take a look around the web and see how poorly these cpu's were received elsewhere.

    My respect for AT is at an all time low - there is no longer any pretence that you aren't an intel shill.
    Reply
  • Hrel - Friday, May 28, 2010 - link

    But it's about F***ing time! Reply
  • zodiacfml - Friday, May 28, 2010 - link

    simply, the new unlocked chips does not offer real advantages compared to their siblings except for dynamic overclocking and the one posted which is little better turboboost speeds.
    yet, the additional cost compared to the performance of AMD's black edition processors is not that reasonable.
    Reply
  • sergiu - Saturday, May 29, 2010 - link

    It would have been nice if we could see the power consumption when dual cascade cooling has been used (both in stock and overclocking). I'm interested to see the leakage scalling with temperature! Reply
  • Rajinder Gill - Saturday, May 29, 2010 - link

    Hi,

    I ran out of time to test any further unfortunately. The emphasis was kept on air/water cooling because it's practical to run 24/7.

    Regards
    Raja
    Reply
  • TheBLK - Saturday, May 29, 2010 - link

    I'll ask again. Unless the screen shots are wrong you used BLK clock to over-clock rather than multiplier on the chip.

    Other reviews kept the BLK at the same value and just used the multiplier and seemed to get higher results.
    Reply
  • Rajinder Gill - Saturday, May 29, 2010 - link

    Yes I did on the 655-K stock VID (added 2 BCLK because the next multiplier up was too far (133 multiples in frequency is a large jump) :
    http://www.anandtech.com/show/3742/intels-core-i56...

    Also describe why BCLK overclocking is not the way to go on the 655K for performance:

    http://www.anandtech.com/show/3742/intels-core-i56...

    Finally the 855K - this chip is limited to 4GHz even on water cooling. BCLK overclocking is not going to change that. 167 BCLK at DDR3 1670 is nowhere near stressful for the Lynnfield IMC. Multiplier overclocking is NOT going to make any difference to the clock speed limitation.

    -Raja
    Reply
  • Rajinder Gill - Saturday, May 29, 2010 - link

    Just for you :)

    http://img7.imageshack.us/f/linpackfailj.jpg/

    That is all the water loop can handle (the chip is drawing over 190W). I can drop the multiplier down to 30 (but then we are back to 4GHz).

    Hope this helps!

    Regards
    Raja
    Reply
  • DJMiggy - Thursday, June 03, 2010 - link

    It seems like you guys used the wrong motherboard or got a dud i7. Other reviewers don't seem to be having as tough a time overclocking these higher. Reply
  • Rajinder Gill - Friday, June 04, 2010 - link

    The motherboard is EVGA's E659 - works fine with my i7 870 ES taking it to 4.4GHz Linpack stable. It's the CPU that is the limiting factor here. Bear in mind that not all articles you've read will have stability checked stability with Linpack as well.

    Later
    Raja
    Reply
  • DJMiggy - Friday, June 04, 2010 - link

    That makes sense. Cool thanks! I appreciate the explanation. Reply
  • ReaM - Saturday, June 05, 2010 - link

    I must say, what a crappy K-series! I can bring every i7 860 up to 4ghz. I have tested many of them, so there is really no reason to put any hope into these Ks. Just buy a regular one.

    My personal sample of 860 runs @ 4200 with 1.29V on air Noctua U12 with low temps.
    Reply
  • ReaM - Saturday, June 05, 2010 - link

    Did you put Load Line Calibration into LVL2?
    I don't know what's that called on EVGA. Enhanced Power Slope. VDrop Adjustment. Lynnfield, unlike Bloomfield, likes their load line to be adjusted.
    Reply
  • Rajinder Gill - Sunday, June 06, 2010 - link

    Makes no difference to the stability of this chip. Reply
  • ehume - Friday, October 08, 2010 - link

    I finally got around to getting the 875k. Using the brand new Real Temp 3.60, I can now adjust the Turbo Boost multipliers so that under load all four cores go to 30x. That means with a bclk of 134MHz I now see a cpu clock range from 1206MHz on idle to 4020MHz on load. Nice.

    But Intel advertised an adjustable memory multiplier as well. Since my memory is rated at DDR3-2000 I would like to push it beyond the 1608MHz that 12x134 allows. So, is it possible to push the memory multiplier beyond 12x? Does the 875k have that in it?

    I have checked a number of reviews and found nothing other than a repetition of Intel's statements that the memory multiplier is unlocked. Well, is it?
    Reply

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