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Google Demands Higher Chip Temps From Intel
JagsLive writes "When purchasing server processors directly from Intel, Google has insisted on a guarantee that the chips can operate at temperatures five degrees centigrade higher than their standard qualification, according to a former Google employee. This allowed the search giant to maintain higher temperatures within its data centers, the ex-employee says, and save millions of dollars each year in cooling costs."
In the past, I've under-clocked primarily for noise benefits. Lower clock->lower temp->slower fam RPM->lower dbSPL.
I'm surprised Google isn't considering moving some of its data centres to Arctic locations where you get cool temperatures year-round.
Don't kid yourself. They probably have. But then, who did you get to work at what would probably be a very remote location?
Additionally, such remote locations may suffer from not enough bandwidth and/or electricity.
Bearded Dragon
This sounds like a scenario where lawyers are trying to act as engineers. That works about as well as you might expect.
There are these engineering things, amusingly called "Schmoo plots", that map out a chip's operating envelope of voltage versus speed versus temperature. From those an engineer can forsee how hot you can run a chip before its rise and fall time margins start to get marginal.
There is very little Intel can do to stretch thing by another 5 degrees. It's not something that can be imposed by fiat. Intel engineers have already juggled all the variables to come up with the best performance possible. SOMETHING is going to have to give. Either the chips will have to be selected and graded for speed, lowering the overall envelope for the chips everyone else gets, or they'll have to fudge some other parameters, hoping nobody will notice, or worse yet they'll tweak some variable right to the edge of raggedness, resulting in worse reliability down the road.
Lawyers and accountants generally don't know you can't have everything. let's hope the engineers educate them.
Traditional 120-many voltage DC power supplies certaily suffer from lesser efficiency at higher temperatures. Running two 4870s on a single 800w power supply probably isn't a good idea, especially if you have a high-powered CPU to go with them. Most quality power supplies will be rated lower than their maximum output to allow for temperature concerns.
These things said, google uses custom power supplies and systems that only run on 12v. These power supplies may be easier to generate in quality batches, but will still be subject to the same efficiency curves.
"And we have seen and do testify that the Father sent the Son to be the Savior of the World"
1 John 4:14
They don't want the chips to get hotter than they already do. They want them to work correctly when they are run hotter. This allows them to use passive cooling in more climates, which saves big bucks on the cooling bill.
The determined Real Programmer can write Fortran programs in any language.
The place was all electric. An incandescent bulb compares favorably to many space heaters in terms of V->heat efficiency, and you get light as a bonus.
It's not just the celerons, its most CPUs. A modern CPU is quite big and contains a lot of components that aren't essential to the operation of the chip. If you disable these, you have a slightly less good chip without the engineering cost of designing a entirely new die layout. AMD takes this to extremes. Their Opterons have 4 cores, three hypertransport connections and a load of cache. If there is a manufacturing flaw in the cache, they are sold as a model with less cache. If it's in the cores, then they are sold as three, two, or single core chips. If it's in the HT controllers then they only support 2- or 4-way multichip configurations. Intel's 486SX line was just a 486 (later renamed the 486DX) where the FPU didn't work.
I am TheRaven on Soylent News
There are two issues with higher operating temp.
One is that you get less drive current from your transistors, so you get less performance (which everyone seems to understand), but this is usually a fairly small effect for 5 degree C.
The _big_ deal with 5 degree C would be electromigration in interconnect metal, which goes up very quickly with temperature. So the difference in failure rates might be quite large.
If there was any deal at all, it's likely that the Intel engineers tried to remove some conservatism from their temperature estimates to see if they could squeeze out 5 degrees from the thermal budget, or perhaps information on the workload itself to get Intel to "bless" the higher data center temperature.
According to microsoft antitrust evidence, it certainly seems like the conspiracy holds some water ;)
http://antitrust.slated.org/www.iowaconsumercase.org/011607/3000/PX03020.pdf
Good people go to bed earlier.
What was even weirder was the i487SX. This was a i486DX with an extra pin. If you had a i486SX system and wanted a FPU you bought the i487SX and plugged it in. Then during boot the i486SX was disabled and the i487SX was used for everything.
Did you take into account that the you'd need to double the resistance of the two resistors to get the right resistance?
Rt = 1/(1/R1+1/R2)
Or you could use two half value units in series.
Either way, the price difference between 5% resisters and 10% resisters is generally NOT a factor of 2, so if you need the closer tolerance, just go with a better band. They come in 20%, 10%, 5%, 2%, and 1%.
On the plus size, the resisters on the whole would be able to withstand almost twice as many watts(the lower resistance one would fail first).
Hmmm...
http://www.alliedelec.com/Resistors
10 kohm, .25 W, 5% = $.05 .25 W, 1% = $.12
10 kohm,
Last I looked, 20% margin resisters were hard to find. Now it looks like 10% are hard as well. Still, even at a bit over double the price at that cheap isn't going to gain you much. The extra soldering is going to be a pain.
I don't read AC A human right
Water is an excellent heat sink, but any company would likely run into serious environmental backlash if they wanted to use a lake or river as their heat sink.
Oh, I dunno, Bethlehem Steel in Indiana (just off of Lake Michigan) did that for years. It was nice going through the outflow in a Hoby Cat... drag your feet through the warm water and enjoy. Good fishing there too.
Coming soon - pyrogyra