Core i7-870 Overclocking And Fixing Blown P55-Based Boards

Status
Not open for further replies.
G

Guest

Guest
FYI: Power consumption of switching cmos silicon increases with the square of voltage, and linear with frequency. The increases shown here seem to be in line with that, rather than the stated decrease in voltage regulator efficiency (which certainly does decrease, but probably much less).
 

Crashman

Polypheme
Former Staff
[citation][nom]dan__g[/nom]FYI: Power consumption of switching cmos silicon increases with the square of voltage, and linear with frequency. The increases shown here seem to be in line with that, rather than the stated decrease in voltage regulator efficiency (which certainly does decrease, but probably much less).[/citation]

Can you turn that into a more accurate estimate than 200W to 240W, where all that can be proven is that it's "high, but less than 240W"?
 

jeffunit

Distinguished
May 19, 2008
117
0
18,680
Are your power consumption measurements of the cpu, dc power or wall socket power? If they are the latter, which I suspect they are, then you have to factor in the power supply efficiency, as 150w socket, means 150w DC.
 

bucifer

Distinguished
May 5, 2009
32
0
18,530
I would be great to see how the more popular i7 860 or at least i5 750 scale with the voltage.
I don't think i7 870 is a popular choice because of it's price (people would go for socket 1336)
 

ctbaars

Distinguished
Dec 16, 2007
496
0
18,810
Thanks for article.
For me - This and previous articles have convinced me to game at stock, w/ tb+ settings on, and a high end GPU card and the i5 is most appropriate for my usage. I need to condition myself to turn off the computer esp. when noone is home.
 

avatar_raq

Distinguished
Dec 8, 2008
532
0
19,010
Although Thomas labels Asrock as "succeeds" I will not buy their motherboards, you'll never know what else this company ignores in the bios, and do you think they would fix that issue if it weren't for THG? After how many failing boards?
 

tecmo34

Administrator
Moderator
[citation][nom]cyberkuberiah[/nom]but some of us would rather give some extra beans and go 920 , and have dual pcie2.0 x16 . a few extra watts doesn't matter too .[/citation]
I agree with you 110%... :D

Also, I would like to see the voltage scaling using the i5 750, as mentioned by bucifer
 
A few extra watts being "used" is fine. A few extra watts being "wasted" is something else entirely.
I don't see a howling difference on these overclocks either. If I bought an i7, that probably means I'd have little reason to OC it.

While ASRock seems to be taking a "successive approximations" approach to improving their products, the ones I've bought so far have all been solid, but any OC has been mild.
And, once again (even if it isn't quite epic), MSI = FAIL.
 
G

Guest

Guest
"The result of huge power losses with moderate performance gains is a decrease in efficiency of over one third at our highest settings"

The first thing i care about when over clocking is being "green"
Why is this even in the report?
 

Crashman

Polypheme
Former Staff
[citation][nom]Antigreen[/nom]"The result of huge power losses with moderate performance gains is a decrease in efficiency of over one third at our highest settings"The first thing i care about when over clocking is being "green" Why is this even in the report?[/citation]

Sometimes you can acgtually gain efficiency when overclocking: This is especially true when voltage levels aren't altered.
 

cyberkuberiah

Distinguished
May 5, 2009
812
0
19,010
[citation][nom]avatar_raq[/nom]Although Thomas labels Asrock as "succeeds" I will not buy their motherboards, you'll never know what else this company ignores in the bios, and do you think they would fix that issue if it weren't for THG? After how many failing boards?[/citation]

i'd go with evga/asus ,and for amd , gigabyte or asus . the crosshair 3 formula is top end at just 200 dollars .
 

warezme

Distinguished
Dec 18, 2006
2,450
56
19,890
Whats wrong with 3.8Ghz? Its good overclock, with minimal stress on all your junk. Why folks have to push their stuff to 4Ghz or higher stressing the hell out of the hardware just for a couple more lousy FPS. I have an X58 that can push voltage and run at 4.2Ghz but voltage and heat requirements go up way to much and only give me a few more FPS. Its not really worth it.
 

grimjester

Distinguished
Sep 24, 2009
24
0
18,510
[citation][nom]Crashman[/nom]Can you turn that into a more accurate estimate than 200W to 240W, where all that can be proven is that it's "high, but less than 240W"?[/citation]

I'm not sure how to interpret the results, but the best fit I get for trying to get a constant W / (GHz * V^2) is a base load of only 7W plus a draw of 36.63-36.72W * frequency in GHz * voltage squared. The fit is fairly accurate; there's a 0,26% difference between the min and the max.

Obviously stuff other than the CPU draws more than 7W, but I don't know enough about the hardware to give an explanation. I'd assume that you get fairly close to 7W + (voltage^2 * GHz * 36,7W) if you measure the draw at other speeds and voltages though.
 
Thanks Crashman, this goes towards a resolution and at least we have a few lower budget boards now that look to be relatively safe.

Didn't you use a different PSU last time? Playing it safe with the higher quality 850HX maybe?
 

Crashman

Polypheme
Former Staff
[citation][nom]Shadow703793[/nom]Can some one please make a list of what motherboards use the problamatic Foxconn socket?[/citation]

ASRock, Asus, Biostar, ECS, Foxconn, Gigabyte, and MSI use Foxconn sockets. Jetway and EVGA use the cheaper Lotes sockets.
 

Crashman

Polypheme
Former Staff
[citation][nom]warezme[/nom]Whats wrong with 3.8Ghz? Its good overclock, with minimal stress on all your junk. Why folks have to push their stuff to 4Ghz or higher stressing the hell out of the hardware just for a couple more lousy FPS. I have an X58 that can push voltage and run at 4.2Ghz but voltage and heat requirements go up way to much and only give me a few more FPS. Its not really worth it.[/citation]

Uh, d00d, let me see if I can explain this in terms you can understand: 1.45V has been used for 45nm Intel processors long enough that it's now a standardized OC test voltage. There are many reasons for it having become this standardized test voltage, including the fact that it's considered the maximum safe voltage in some Intel documentation, that it's the maximum voltage most processors can run using above-ambient cooling, that it's the spot just before power consumption spikes, etc. It makes sense, and because it's NOT extreme, was never extreme, was never intended to be extreme, and is in no way extreme, it's something that any overclocking motherboard should tollerate.

We understand that cheap boards exist. If you're going to market a cheap board towards low-cost overclocking, you need to put in over-current protection. If you're going to market an even cheaper board with no protection, you need to disable the overclocking features.

It's one way or the other, when it comes to overclocking either do it right or don't do it at all. Half-fast solutions aren't acceptable in the overclocking market. It's a quality issue, and Tom's Hardware has tested MANY high-quality budget parts in the past.

There's no excuse to cut quality when you can instead cut features to produce a cheap product. IE, if you really really really wanted to make a board that could only do 1.35V before blowing the VRM, and really wanted to sell it without overcurrent protection, you'd really really really want to limit the BIOS settings to 1.35V. Because when you didn't, you'd get caught with your pants down by a site such as this one.

To not report such a finding would be proof of a lack of integrity. To give up testing at this setting would be to cave in for low-quality products at the expense of not revealing the superiority of high-quality products. The reader isn't served, the industry is disserviced, everyone loses.


[citation][nom]Proximon[/nom]Thanks Crashman, this goes towards a resolution and at least we have a few lower budget boards now that look to be relatively safe.Didn't you use a different PSU last time? Playing it safe with the higher quality 850HX maybe?[/citation]

Nah, same power supply since September, might have forgotten to change the model in the setup table.
 

JeanLuc

Distinguished
Oct 21, 2002
979
0
18,990
[citation][nom]cyberkuberiah[/nom]but some of us would rather give some extra beans and go 920 , and have dual pcie2.0 x16 . a few extra watts doesn't matter too .[/citation]

Why do you want dual x16 slot when it offers no extra benefit? You might want to give this a read http://www.techpowerup.com/reviews/AMD/HD_5870_PCI-Express_Scaling/7.html before you start clicking that thumbs down button, and if you do disagree please tell me why I'm wrong.

Even the most powerful card in the world can't saturate an x8 slot according to that source.
 

KenZen2B

Distinguished
Oct 27, 2009
116
0
18,710
Thermalright’s MUX-120 cooler is barely big enough to cool our fully-overclocked i7-870 processor at 1.45V under the stress of eight Prime95 threads, even with an ambient temperature of 22 degrees Celsius.

1. If you changed out the stock cooler for a better one (say a Thermalright’s IFX-14) allow your system to last longer while running at the 1.45V setting over the long term?

2. Is there any reason to believe that reducing the ambient air temperature to 0 C would reduce power consumption and increase the performance gains realized?

Your articles provide great information.
 

blacksun

Distinguished
Nov 4, 2009
9
0
18,510
For Silicon, the leakage current will be increased by higher voltage and temperature. For deep sub-micron process like 45nm, there is the serious BJT effect. The MOS leakage current will increase exponatially and near to avalache breakdown. So if power consumption is out of control like over 150W or above, 1156-pin CPU spec. is 95W, the CPU is very dangerous. What ASRock P55 Pro do is not only protecting their M/B but also protecting 1156-pin CPU & CPU socket.
 

Crashman

Polypheme
Former Staff
[citation][nom]KenZen2B[/nom]1. If you changed out the stock cooler for a better one (say a Thermalright’s IFX-14) allow your system to last longer while running at the 1.45V setting over the long term?2. Is there any reason to believe that reducing the ambient air temperature to 0 C would reduce power consumption and increase the performance gains realized?Your articles provide great information.[/citation]

1.) 1.45V should be possible over several months, but it would probably take something larger than the IFX-14. A dual-fan radiator with good water pump and block would probably handle the job. Of course, none of those address the VRM problem.

2.) There's no reason to believe computational performance would improve, though power consumption should go down.
 

mozaix

Distinguished
Nov 4, 2009
2
0
18,510
Great article!

I am glad Asus still delivers quality. Been 5 years since I did last upgrade. I felt my choice was between Asus or Gigabyte.

It would be nice if you could do the same test with the i5-750 and i7-860 cpu also. I think most people who choose the 1156 platform will go for a more affordable cpu.
 
Status
Not open for further replies.