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Comment Re:Correct me if I'm wrong... (Score 1) 298

http://en.wikipedia.org/wiki/M...

The F-4's biggest weakness, as it was initially designed, was its lack of an internal cannon. For a brief period, doctrine held that turning combat would be impossible at supersonic speeds and little effort was made to teach pilots air combat maneuvering. In reality, engagements quickly became subsonic, as pilots would slow down in an effort to get behind their adversaries. Furthermore, the relatively new heat-seeking and radar-guided missiles at the time were frequently reported as unreliable and pilots had to use multiple shots (also known as ripple-firing), just to hit one enemy fighter. To compound the problem, rules of engagement in Vietnam precluded long-range missile attacks in most instances, as visual identification was normally required. Many pilots found themselves on the tail of an enemy aircraft but too close to fire short-range Falcons or Sidewinders. Although by 1965 USAF F-4Cs began carrying SUU-16 external gunpods containing a 20 mm (.79 in) M61 Vulcan Gatling cannon, USAF cockpits were not equipped with lead-computing gunsights until the introduction of the SUU-23, virtually assuring a miss in a maneuvering fight. Some marine corps aircraft carried two pods for strafing. In addition to the loss of performance due to drag, combat showed the externally mounted cannon to be inaccurate unless frequently boresighted, yet far more cost-effective than missiles. The lack of a cannon was finally addressed by adding an internally mounted 20 mm (.79 in) M61 Vulcan on the F-4E

The notion that air to air combat is going to be missile based implicitly assumes the US will only fight countries which are enormously inferior in military capabilities or where people don't want to fight - e.g. Iraq, Libya etc. Put the US in a battle with North Korea, China, Russia etc and things will change.

Comment Re: WTF! No posts?!?! (Score 0) 217

LTTE is Long TTerm Evolution, a standard for wireless communication of high-speed data for mobile phones and data terminals. It is based on the GSM/EDGE and UMTS/HSPA network technologies, increasing the capacity and speed using a different radio interface together with core network improvements. The standard is developed by the 3GPP (3rd Generation Partnership Project) and is specified in its Release 8 document series, with minor enhancements described in Release 9.

Comment Re: approximately the resolution of an adult eye @ (Score 1) 217

How 400-600 entered the conversation is beyond me. The percentage of people who can visually tell the difference between a 300 dpi output and anything higher than that is very, very small. The number of people who can spot the difference at 400+ is not even a consideration for discussion. I'm sure there are some who can but don't even vaguely think that they in any way represent the norm.

What about all the giant squids browsing the Internet from R'lyeh? They've got eyes the size of dinner plates so their vision must have superb angular resolution?

Comment Cx power state (Score 1) 173

Does anyone else think that Intel should introduce power states like you get in embedded systems where you have 'rules' like "reprogram the SDRAM controller and bus interface controller. Oh and make sure there's no AHB bus activity (e.g. access to SDRAM or Flash memory) at all when you do it, otherwise the whole system will lock up hard". Traditionally these rules are discovered empirically and are documented by sweary comments in check ins.

The reason is

1) It'll keep those bastards at the OEMs on their toes.

2) More work for consultants working on Bioses, the ACPI standard etc.

Actually support for ARM systems means this sort of thing will probably happen

http://mjg59.dreamwidth.org/26...

Supporting Device Tree would require Microsoft to rewrite large parts of Windows, whereas mandating UEFI and ACPI allowed them to reuse most of their existing Windows boot and driver code. As a result, largely at Microsoft's behest, ACPI 5 has grown a range of additional features for describing things like GPIO pinouts and I2C connections. Whatever your weird device layout, you can probably express it via ACPI.

Obviously doing this sort of thing via ACPI methods adds and additional - and from a consultancy point of view entirely welcome - level of fuck to "reprogram the SDRAM controller and bus interface controller. Oh and make sure there's no AHB bus activity (e.g. access to SDRAM or Flash memory) at all when you do it, otherwise the whole system will lock up hard".

I.e. if you didn't have ACPI but rather just had a hard coded chipset specific hacks file, you could just have a few lines of assembler to poke the hardware in the right order and stick in in TCM (or if you're in a bad mode cunningly aligned to a cache line). Now with ACPI you're supposed to use AML bytecode which is run by - I shit you not - an interpreter in the OS.

Comment Re:Using 'songs' as units of measurement? (Score 1) 100

Most mp3's are going to be somewhere between 3 and 10 MB. That's close enough to give a rough estimate of how many "songs" you can fit on your mp3 player.

MP3 player manufacturers used 'You Suffer' by Napalm Death encoded at 32kbps as their reference MP3.

http://en.wikipedia.org/wiki/Y...

"You Suffer" is a song by the British grindcore band Napalm Death, from their debut album, Scum. The song has earned a place in the Guinness Book of Records as the shortest recorded song ever. It is precisely 1.316 seconds long/quote.

It's like hard disk manufacturers using the decimal version of a megabyte to make their drives look bigger.

Comment Re:454 / 16 (Score 2) 116

Like most utopias it's probably got a downside.

The fees will go up and those who can't afford them will be converted into serfs or indentured labourers. Finally the CSA (Confederate States of America) will arise again with the newly recruited serfs growing cotton on those 20 acres.

Comment Re:seperate mobile GPU's is declining market (Score 1) 83

I would imagine Nvidia are very uncomfortable with the way their market has been contracting over the last couple of years.

At some point enough x86/x64 patents will expire that Nvidia will be able license the remaining ones and so an x64 chip of their own.

Or alternatively they could sell Arm+GPU SOCs instead - arguably Arm+GPU is a better bet than x64+GPU because the sales of phones and tablets will exceed the sales of x64 PCs. Of course the margins are likely to be thinner because there's a lot of competition in the Arm SOC market - Apple and Samsung have their own in house designs and outside that it looks like Qualcomm have most of the rest of the market.

Still it's not like AMD is doing very well competing with Intel. And the reason Qualcomm do so well is because they design their own Arm microarchitectures - Scorpion and Krait were both designed in house and were higher performance than the best Arm designed microarchitecture. So I guess NVidia could be aimed to compete with Qualcomm since Denver is in house too.

Actually Apple A6 and A7 chips are like this too. Apple have an Arm license but the chips are designed in house. So it seems like of the Arm SOCs that actually sell well only Samsung is using Arm's designs and only in some markets

E.g.

http://en.wikipedia.org/wiki/S...

Galaxy S4 models use of one of two processors, depending on the region and network compatibility. The S4 version for North America, most of Europe, parts of Asia, and other countries contains Qualcomm's Snapdragon 600 system-on-chip, containing a quad-core 1.9 GHz Krait 300 CPU and an Adreno 320 GPU. The chip also contains a modem which supports LTE. Other models include Samsung's Exynos 5 Octa system-on-chip with a heterogeneous CPU. The octa-core CPU comprises a 1.6 GHz quad-core Cortex-A15 cluster and a 1.2 GHz quad-core Cortex-A7 cluster. The chip can dynamically switch between the two clusters of cores based on CPU usage; the chip switches to the A15 cores when more processing power is needed, and stays on the A7 cores to conserve energy on lighter loads

So there are two versions. A Qualcomm Snapdragon one for the US and Europe and an Exynos one for Asia. The Exynos one uses Cortex-A15 and Cortex-A7 in a BIG.little configuration.

Unfortunately they fucked up the big.LITTLE configuration

http://www.anandtech.com/show/...

The Exynos 5410 saw limited use, appearing in some international versions of the Galaxy S 4 and nothing else. Part of the problem with the design was a broken implementation of the CCI-400 coherent bus interface that connect the two CPU islands to the rest of the SoC. In the case of the 5410, the bus was functional but coherency was broken and manually disabled on the Galaxy S 4. The implications are serious from a power consumption (and performance) standpoint. With all caches being flushed out to main memory upon a switch between CPU islands. Neither ARM nor Samsung LSI will talk about the bug publicly, and Samsung didn't fess up to the problem at first either - leaving end users to discover it on their own.

You can see the results here

http://www.gsmarena.com/samsun...

The Qualcomm one has much better talk time - almost twice as much.

You have to wonder what the hell has happened to Arm to be honest. It seems like Apple (A6, A7) and Qualcomm (Scorpion, Krait) do a much better job at Arm core design than Arm/Samsung.

It'll be interesting to see battery life tests on the Snapdragon 801 and Exynos 5422 versions of the S5 to see if Samsung have got big.LITTLE working like it is supposed to. Actually I wonder whether big.LITTLE is even necessary - it seems like it would be much easier to just have the big core and scale the CPU frequency. The S5's CPUs are 2.5 GHz quad-core for the Snapdragon variant 2.1 GHz quad-core Cortex-A15 and 1.5 GHz quad-core Cortex-A7 for the Exynos variant.

That's quite a step up from the S4 so you could probably run them at a much lower clock frequency most of the time. I guess the problem is that a Cortex-A15 uses more juice when run at a low speed than an Krait and big.LITTLE (aka 'use an A7 instead when performance isn't critical') was a sort of band aid for this.

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