Search Amazon.com:
Register a SA Forums Account here!
JOINING THE SA FORUMS WILL REMOVE THIS BIG AD, THE ANNOYING UNDERLINED ADS, AND STUPID INTERSTITIAL ADS!!!

You can: log in, read the tech support FAQ, or request your lost password. This dumb message (and those ads) will appear on every screen until you register! Get rid of this crap by registering your own SA Forums Account and joining roughly 150,000 Goons, for the one-time price of $9.95! We charge money because it costs us $3,400 per month for bandwidth bills alone, and since we don't believe in shoving popup ads to our registered users, we try to make the money back through forum registrations.
«145 »
  • Post
  • Reply
Alereon
Feb 6, 2004

For me but LEFTHANDED

Combat Pretzel posted:

What does the BIOS have to do with anything beyond initializing device parameters during POST? Once the NT kernel's booting, it is entirely out of the picture.
Have you seen the wealth of power-related options on Haswell systems with UEFI? You can override many of them with the Intel Extreme Tuning Utility, but unless you take the time the defaults set by the motherboard manufacturer will apply. Microsoft sure as hell isn't tweaking the VRM frequency.

Note that in some cases default settings may not even match Intel's specs, for example the Multi-Core Enhancement on most overclocking boards where the CPU defaults to its highest single-core turbo bin at all load levels.

Alereon fucked around with this message at Aug 31, 2014 around 19:30

Adbot
ADBOT LOVES YOU

movax
Aug 30, 2008



Combat Pretzel posted:

What does the BIOS have to do with anything beyond initializing device parameters during POST? Once the NT kernel's booting, it is entirely out of the picture.

Most board vendors will start from the CRB or similar reference source drop from AMI, Phoenix, etc. I'm most familiar with AMI and their APTIO product since that's what my company bought and I wrote/ported for our platform. There's a lot of effort that can be expended (if you're a bigger company and have BIOS engineers on staff) to optimize power-related behavior above and beyond from what the reference platform does. Power related stuff can be notoriously finicky, as by its nature, managing several different possible states of power, where various memories and peripherals could be unavailable, and there are a variety of way to enter / exit each state.

Then you have to validate all the of the above, which takes time and effort; that's where the larger, better companies come out ahead IMO.

Combat Pretzel
Jun 23, 2004

No, seriously... what kurds?!

Alereon posted:

Have you seen the wealth of power-related options on Haswell systems with UEFI? You can override many of them with the Intel Extreme Tuning Utility, but unless you take the time the defaults set by the motherboard manufacturer will apply. Microsoft sure as hell isn't tweaking the VRM frequency.
OK, but these things happen and are set up during POST. The kernel, once running, is not going to call into the UEFI BIOS though. So how do DPC latencies factor into this? If the Xonar driver drama taught me anything, it's seems mostly a driver issue.

Alereon
Feb 6, 2004

For me but LEFTHANDED

Combat Pretzel posted:

OK, but these things happen and are set up during POST. The kernel, once running, is not going to call into the UEFI BIOS though. So how do DPC latencies factor into this? If the Xonar driver drama taught me anything, it's seems mostly a driver issue.
There are a number of settings that affect DPC, some of which may or may not be exposed to the user. There are definitely event timer settings, and there's likely settings similar to pollrates for integrated peripherals that let the motherboard manufacturer balance performance and latency. You can see measurable and meaningful differences in DPC latency between boards with similar integrated peripherals. This did get a lot better with Z97 boards, and it will be interesting to see how X99 boards stack up with eachother.

movax
Aug 30, 2008



Combat Pretzel posted:

OK, but these things happen and are set up during POST. The kernel, once running, is not going to call into the UEFI BIOS though. So how do DPC latencies factor into this? If the Xonar driver drama taught me anything, it's seems mostly a driver issue.

EFI does provide a table in memory for a host kernel to utilize for certain features, if so desired. EFI_RUNTIME_SERVICES if I recall correctly. It's nothing too exciting, but the kernel can definitely dive into and execute code that is stored as part of system firmware.

The Lord Bude
May 23, 2007

I'M DISAPPOINTED THAT CORTANA WILL BE A CIRCLE AND NOT THE ACTUAL SEXY WOMAN FROM THE GAME.


Alereon posted:

Those cheap Asrock boards aren't any good, though. There are a few factors that go into whether a motherboard is good or not, not all of them are easy to measure or market, and features are the least important. Here's the basic order of importance of considerations for a motherboard:

1. Design, trace layout, and overall engineering
2. Component selection and quality
3. BIOS engineering and optimization
4. Features

Audio quality is the best, most easily measured example of #1. When you measure the audio output quality of a motherboard you're measuring how well the designer isolated the analog audio signals from the other traces and sources of interference on the board. Poor isolation causes audible hiss and noise in the background of audio that changes based on system activity, which can be very annoying. The audio section from the Asrock Z97 Extreme 6 upthread illustrates this well, all the boards with the same audio chip get similar dynamic range scores, but despite being a higher-end board the Asrock Z97 Extreme 6 has THD+N scores similar to mid-range mothebroards. Their less expensive boards would be further down that chart.

Even if you don't care about audio, those same factors apply to the signal traces you DO care about, particularly those between the RAM and the CPU. The quality of the signal between the RAM and CPU is the single greatest factor affecting system stability, and it's why RAM that works just fine may fail in a lower-quality board. It's hard to measure this directly, but memory overclocking results are a good indicator, and this is an area where Asus has excelled for a few generations.

Power delivery quality is a combination of the first and second factors. The number of VRM phases and the quality of the capacitors selected is a simple component choice issue, using thick enough traces to carry power from the top of the board to the PCI-Express slots is more layout and design. Cheap boards like that have extra power connectors near the PCI-Express slots so they can cheap out on those traces. Like all things this is a matter of degree, Gigabyte boards go so cheap you always have to have the extra power cable connected for stable operation, that may not be the case with only one or two cards on that Asrock board.

Some other component selection choices are things like the network adapter. Good boards use Intel, low-end boards use Realtek, garbage boards use KillerNIC chipsets. The audio chipset itself is pretty standard these days and doesn't make much difference.

BIOS quality comes down to three main factors, POST time, DPC latency, and power usage. POST time is how long it takes the system to start loading the operating system from the time you press the power button. Better motherboards initialize faster, though boards with more hardware take longer to initialize (though usually you can get this time back by disabling that hardware). DPC latency is how long (in microseconds) the system takes to respond to an interrupt, and depends on component selection, drivers, and BIOS optimizations. A board with poor DPC latency can feel noticeably laggy. Asrock has actually been pretty good compared to other brands on both POST time and DPC latency in recent generations, though these new boards remain to be tested. BIOS optimizations also play the biggest role in power consumption, though this isn't very relevant for desktop users.

Only now do we get to the features that manufacturers use to segment their products. There's some overlap here with component selection for things like VRM phases, as the number of phases is usually a selling feature for the board. Similarly, the presence of ports or controller chips is both a component and feature selection. I personally think the fan control that Asus offers on its boards is pretty drat compelling, and I like Asus's UEFI firmware, but these aren't really the actual reason to buy the boards. Then again Asrock does have a dehumidifier

http://www.youtube.com/watch?v=-mQfFVT4tT8
(The theory is that the hot air in your case can hold more moisture than the cooler air outside, so if you shut your system down moisture could condense when the hot air cools. This runs the fans to blow the hot air out of the system before it cools. It can also run daily if your computer was turned off, to ventilate the system as the day cools down for the same reason. You decide whether this is crazy-talk!)

This is excellent information. Have there been any reviews of asrock boards compared to Asus boards that analyse these issues at that level? I ask more for 1150 boards than anything else, because we tend to steer people towards asrock in the parts picking thread because you tend to save money and get higher grade audio chips in asrock boards vs similar Asus boards and I'm wondering whether we should rethink that. I've never seen an asrock board requiring extra PCIe power connectors like gigabyte do though.

BurritoJustice
Oct 9, 2012



I don't think we should stop recommending ASRock based entirely off speculation and anecdotes, ignoring the multitudes of objective reviews showing them to be good, excellent even. The only spec in that review that the ASRock is not fantastic is a single audio benchmark where it is middle off the pack instead of the absolute best (like it is for DPC latency.

The added connector for PCI-E power is not an indicator of PCI-E trace quality, it's a feature. It's useful for stability when you have a whole pile of add in cards each requesting 75w from the slot. It's entirely optional. You know what else has one? The ~Asus~ Rampage V Extreme super ultra gamer edition.

Alereon
Feb 6, 2004

For me but LEFTHANDED

The Lord Bude posted:

This is excellent information. Have there been any reviews of asrock boards compared to Asus boards that analyse these issues at that level? I ask more for 1150 boards than anything else, because we tend to steer people towards asrock in the parts picking thread because you tend to save money and get higher grade audio chips in asrock boards vs similar Asus boards and I'm wondering whether we should rethink that. I've never seen an asrock board requiring extra PCIe power connectors like gigabyte do though.
Anandtech's reviews are pretty good, as are TechPowerUp's. They do DPC latency, audio quality, and POST time benchmarks that can be hard to find elsewhere, and Anandtech in particular has done reasonably good vDroop tests, including discovering Gigabyte's fake voltage readings. I think choosing a board comes down to picking a range that suits your intended purpose, then picking a sweet spot within that range that best matches your desired features and price. For example, most Asus channel boards have pretty similar audio section layout with good isolation, but you can clearly see a decline in the number and size of capacitors as you move down in price.

BurritoJustice posted:

I don't think we should stop recommending ASRock based entirely off speculation and anecdotes, ignoring the multitudes of objective reviews showing them to be good, excellent even. The only spec in that review that the ASRock is not fantastic is a single audio benchmark where it is middle off the pack instead of the absolute best (like it is for DPC latency.
Like I said above, the point is that the quality of isolation of the audio traces tells you a lot about the quality of the board in general. That's a board loaded with typically higher-end features, but with a mid-range price corners have been cut to get there. Some of those, like the limited number of VRM phases, are pretty reasonable. Poor quality trace layout and isolation, which you see as that poor THD+N result, is not. The difference between "good" and "crap" is making the right tradeoffs, and lower quality for more features is almost never the right trade.

quote:

The added connector for PCI-E power is not an indicator of PCI-E trace quality, it's a feature. It's useful for stability when you have a whole pile of add in cards each requesting 75w from the slot. It's entirely optional. You know what else has one? The ~Asus~ Rampage V Extreme super ultra gamer edition.
Extreme high-end boards typically do have at least one additional 8-pin power connector to handle a large number of cards. Very low-end boards on which a lot of corners have been cut have a SATA power connector or a molex connector. The $400 Asus X99 Deluxe does not have any additional power connectors and it is meant to take four PCI-E 3.0 x16 cards, plus an x4. It has the build quality to power its slots without additional power connectors, the Asrock board does not. Consider that Gigabyte boards with a SATA power connector require it to be connected for stable operation with even a single videocard, despite the manual claiming it is for multi-GPU.

the1onewolf
Dec 19, 2013

Architect of all things Timey-Wimey


Intel's naming schemes always gives me a headache.
I wonder how the new Broadwell shrink is going to stack up against the Haswell-E stuff.
Considering how late it is into 2014, is the new Skylake architecture is going to be pushed back pretty late in 2015?

BurritoJustice
Oct 9, 2012



Alereon posted:

Like I said above, the point is that the quality of isolation of the audio traces tells you a lot about the quality of the board in general. That's a board loaded with typically higher-end features, but with a mid-range price corners have been cut to get there. Some of those, like the limited number of VRM phases, are pretty reasonable. Poor quality trace layout and isolation, which you see as that poor THD+N result, is not. The difference between "good" and "crap" is making the right tradeoffs, and lower quality for more features is almost never the right trade.
Extreme high-end boards typically do have at least one additional 8-pin power connector to handle a large number of cards. Very low-end boards on which a lot of corners have been cut have a SATA power connector or a molex connector. The $400 Asus X99 Deluxe does not have any additional power connectors and it is meant to take four PCI-E 3.0 x16 cards, plus an x4. It has the build quality to power its slots without additional power connectors, the Asrock board does not. Consider that Gigabyte boards with a SATA power connector require it to be connected for stable operation with even a single videocard, despite the manual claiming it is for multi-GPU.

You are making some interesting jumps in logic here. While the audio results aren't fantastic, they certainly aren't terrible. The isolation of audio components is not something that depends just on quality of tracings, but also how they are routed, nearby components, shielding etc. By the logic of poor tracing solely from that result, we shouldn't recommend boards from MSI, EVGA, Gigabyte and ASUS as well, as they post motherboards with worse distortion figures than the Extreme6. I also find your comment about low end boards and molex connectors amusing, considering that the aforementioned Rampage V Extreme uses a molex connector. Anecdotally, I remember it being quoted of Asus and ASRock that they both choose molex for auxiliary power as it is more commonly a spare connector on modern power supplies, compared to PCI-E connectors which are commonly either all used, or on long dual connectors for graphics cards.

Like I said earlier, the additionally power connector is a feature (ignoring lovely outlying gigabyte boards) that is popular amongst enthusiasts. It is definitely not needed for normal operation on the ASRock boards, as quoted by reviewers and also from my own anecdote (my friend has an Extreme4 with two 780s on it without the connector merely because he did not want to have to route it). It is commonly used for one of three situations; 3 or 4 card setups, insane GPU overclocking/volting situations, and mining setups with a large amount of cards without PCI-E connectors that will stress the PCI-E power draw immensely (think 6 or 7 750ti's). In 99% of these situations even, it is merely placebo as well to have an effect. It certainly is popular in crowds such as [H]ardForum, overclock.net etc. I'd be willing to bet that ASRock gets more sales because of it.



EDIT: I forgot to address your comment on power phases. If you could expand on this, that would be good. It is an interesting comment considering that the Extreme6 has a 12 Phase design with good Nippon Chemi-Con caps rated at 12k hours. The equivalent Asus board, the Z97-A (which is more expensive), has an 8 phase design with 10k hour rated caps.

BurritoJustice fucked around with this message at Sep 1, 2014 around 09:05

BobHoward
Feb 13, 2012

Special Operations Executive
Q Section




Alereon posted:

Extreme high-end boards typically do have at least one additional 8-pin power connector to handle a large number of cards. Very low-end boards on which a lot of corners have been cut have a SATA power connector or a molex connector. The $400 Asus X99 Deluxe does not have any additional power connectors and it is meant to take four PCI-E 3.0 x16 cards, plus an x4. It has the build quality to power its slots without additional power connectors, the Asrock board does not. Consider that Gigabyte boards with a SATA power connector require it to be connected for stable operation with even a single videocard, despite the manual claiming it is for multi-GPU.

75W per card * 5 = 375W
Haswell-E: 140W, potentially a lot more if overclocking
Total budget (ignoring anything else that might need to draw from 12V going to the motherboard): 515W (no OC), 600+ (OC)

EATX main connector: two 12V pins, 8A max each (that being the Molex connector's rated limit per pin, wire gauge matters too)
8-pin EATX 12V connector: four 12V pins, 8A max each

6*8A*12V = 576W

Safe if not overclocking, but if you are? Forget about it. Asus is relying on the fact that most high end GPUs draw very little power through the PCIe slot.

Also your theory that adding (relatively expensive) molex connectors is a viable way of reducing the total board cost by saving money on traces is somewhat unlikely. A plane of generic 2oz copper can carry rather a lot of current. Perhaps there are some cheapass motherboards which actually do try to save insignificant amounts of money by using blank copper clad with thinner-than-normal plating, but this will probably cause CPU issues long before PCIe. CPUs are a much tougher power delivery problem: low voltage at ridiculously high amps, with vastly less tolerance for voltage droop.

Daviclond
May 20, 2006

Bad post sighted! Firing.

Alereon posted:

Then again Asrock does have a dehumidifier

http://www.youtube.com/watch?v=-mQfFVT4tT8
(The theory is that the hot air in your case can hold more moisture than the cooler air outside, so if you shut your system down moisture could condense when the hot air cools. This runs the fans to blow the hot air out of the system before it cools. It can also run daily if your computer was turned off, to ventilate the system as the day cools down for the same reason. You decide whether this is crazy-talk!)

Yeah this sounds like a load of poo poo. The hot air in your case arrived through the front vent as ambient air that is relatively cold and relatively low in moisture. There is absolutely no problem whatsoever with it entering the case, heating up, and then cooling down over time. If it can hold the moisture on its way in at the cold inlet temperature then it can hold the moisture without any condensing an hour later when it's cooled down. The only problem would be if it was in contact with a source of liquid water *after* it was heated up inside the case, which is obviously not a scenario that is often encountered inside a functioning computer

The daily ventilation cycle is dubious for the reason that there should already be ample ventilation through natural air movement to prevent condensation on the inside of the case. I dunno maybe if you live in a jungle or something with crazy humidity cycles it's valid. I can't say for sure because humidity does appear to be a valid concern in datacentres and gets monitored for example, but I don't see a consumer's PC having sufficiently restricted airflow to cause condensation inside the case. Condensation forms on your windows and the inside of exterior walls, not your coffee table.

The little bit of autism in me that got me through my engineering degree is also upset they're calling it a "dehumidifier" when there's no dehumidification being carried out, just air circulation.

Panty Saluter
Jan 17, 2004

A Casual Gay


If your house is that humid maybe you should invest in some weatherstripping

Sidesaddle Cavalry
Mar 15, 2013

Yep, that shirt says ほ alright.


Panty Saluter posted:

If your house is that humid maybe you should invest in some weatherstripping

A lot of places where the weather actually is that humid, there isn't enough infrastructure for weatherstripping to be available for the general public to buy

But yes, this is snake oil.

Sidesaddle Cavalry fucked around with this message at Sep 2, 2014 around 01:24

Combat Pretzel
Jun 23, 2004

No, seriously... what kurds?!

How does the turbo on Intel CPUs work, anyway? It's the maximum frequency it can run on the standard voltage, but does only partially because of thermal issues? With proper cooling a CPU can run on turbo all day long?

thetechnoloser
Feb 11, 2003

Say hello to post-apocalyptic fun!

Combat Pretzel posted:

How does the turbo on Intel CPUs work, anyway? It's the maximum frequency it can run on the standard voltage, but does only partially because of thermal issues? With proper cooling a CPU can run on turbo all day long?


Yup. I run a i5 4670k at 'full speed' with an OC at 42x (4.2ghz) all day long, no problems. For a CPU that's marked as 3.4ghz.

Factory Factory
Mar 19, 2010

I can do sex. It's just alien sex.


Combat Pretzel posted:

How does the turbo on Intel CPUs work, anyway? It's the maximum frequency it can run on the standard voltage, but does only partially because of thermal issues? With proper cooling a CPU can run on turbo all day long?

Some motherboards break out the individual parameters, so I actually know this:

The are three major groups of settings: clock multipliers, short-term turbo, and long-term turbo.

Clock multipliers are pretty self-explanatory - that's just the maximum clock rates for 1, 2, 3, 4 etc. cores at once. On e.g. a 4790K, I think the stock is 44/43/42/42 1/2/3/4-core turbo, with a 40 base clock multiplier. Times 100 MHz baseclock, and that's where you get 4.0 to 4.4 GHz.

The short- and long-term turbo states have a few different parameters. There's a maximum additional voltage offset (and sometimes some intermediates are specified), and there are targets for both chip power draw (TDP) and chip temperature. Then there is a maximum state time (I think it's 0-255 milliseconds short-term and 0-255 seconds long-term) - this is the longest the chip can go before re-evaluating how close it is to the TDP and temperature targets.

So when the chip notices that it is under load and below the temp and TDP targets, it will jump into the short-term state. This usually brings the temp and TDP targets right up, because that state is configured to be very high power draw for a short amount of time, and that triggers dropping into a more-sustainable long-term turbo state. The long-term turbo state is not as aggressive and, on mobile chips., will involve a clock speed drop. On desktops, sometimes not - they have a lot of room to play with on TDP and temperature compared to mobile chips.

Assuming the system can't sustain turbo after this, it will then proceed to jump up and down between base and intermediate turbo states as temperature and power allow.

Here's what that looks like on Surface Pro 2 with a 1.9-2.9 GHz i5 with a 15W TDP, via AnandTech:



When the GPU is mostly doing nothing, you can see the IA cores constantly hopping from long-term turbo into short-term. When the GPU gears up for video chat, you can see the chip power increase hugely in the short-term turbo state, but the temperature is under control enough that short-term turbo can be sustained for ~30 seconds.

But when temperature isn't under control, Turbo stops. Case in point, the same chip in a Surface Pro 3:



By the third loop of the video chat test, temperature gets high enough that short-term turbo is never entered, and CPU frequency is flat in an intermediate turbo state.

In previous runs of the video chat on the SP3, you can see the CPU clock drop as far as the base 1.9 GHz clock speed as the GPU's needs temporarily dominate the remaining thermal budget.

Factory Factory fucked around with this message at Sep 1, 2014 around 15:57

Panty Saluter
Jan 17, 2004

A Casual Gay


thetechnoloser posted:

Yup. I run a i5 4670k at 'full speed' with an OC at 42x (4.2ghz) all day long, no problems. For a CPU that's marked as 3.4ghz.

What cooler are you using? I could always buy another Hyper 212 but that's kinda boring

thetechnoloser
Feb 11, 2003

Say hello to post-apocalyptic fun!

Panty Saluter posted:

What cooler are you using? I could always buy another Hyper 212 but that's kinda boring

NZXT Kraken X41. Not sure if that's one of SH/SCs favs ATM, but it's worked well for me.

http://www.microcenter.com/product/...quid_CPU_Cooler

track day bro!
Feb 17, 2005

frutella'sa badman sweet ya get me



Panty Saluter posted:

What cooler are you using? I could always buy another Hyper 212 but that's kinda boring

I've got the same cpu running at 4.4 with a NH-U12S after several prime95 and ibt runs its fine.

Adbot
ADBOT LOVES YOU

1gnoirents
Jun 28, 2014


I really enjoyed reading the motherboard information.

  • 1
  • 2
  • 3
  • 4
  • 5
  • Post
  • Reply
«145 »