Via Unveils 1-Watt x86 CPU

DeviceGuru writes "Taiwanese chip and board vendor Via Technologies has introduced a new ultra-low voltage (ULV) processor aimed at industrial, commercial, and ultra-mobile applications. Touted as the world's most power-efficient x86-compatible CPU, the 500MHz 'Eden ULV 500' processor debuted at an Embedded Systems Conference in Taipei this week. Via says its chip draws a minimum of 0.1 Watts, when idle, and a maximum of 1 Watt, making it a great candidate for consumer electronics devices such as UMPCs, PVRs, and such."

Comments

laptop anyone

[IceFox]

A nice laptop cpu if I ever saw one.

Re:laptop anyone

[cnettel]

Yes and no. If we're going to have a backlit screen anyway (even with LEDs), we can only gain so much by reducing the CPU consumption. Amdahl's law and all that. I think the summary is quite right in pointing out UMPCs and similar devices instead.

A really low-power Dothan or single-core Yonah will sure draw a few multiples of this beast, but they will do so while giving much better performance.

Re:laptop anyone

[arivanov]

Not really.

I have used every single Via CPU from the original Eden 533 up to 1.5GHz C7 and IMO the C3-C5 spec Edens are just about useful for a dedicated appliances, small firewalls, small specialised servers and such. They do not have enough grunt for a laptop. The fact that most of them have are shipped bundled with relatively weak video does not really help either. Even the mpeg support on some motherboards cannot really help. Xterm is probably the most you can do with them as far as clients are concerned. Still better than similarly clocked Crusoe though (now that is a drag of all drags).

C7 is a completely different beast. This is probably the best CPU for a corporate laptop out there at the moment. A laptop is worthless without a "link to the mothership". Intel Core and AMD have to use CPU resource to do all of the encryption and decryption. This may amount to 30-40% of your CPU on a 54G wireless lan. Compared to that Via C7 has hardware AES acceleration so you can actually protect your traffic properly while using less than 1% of your CPU. It also has enough grunt to run most common road warrior apps at acceptable speeds. It is a pity it is not available as a laptop choice anywhere outside the far east.

Re:laptop anyone

[arivanov]

By what I recall - no, but I have not looked at the OpenSSH latest and greatest (it has been 6+ months since I looked at this).

The reason is that at least as of the versions present in major distros openssh does not for some reason support openssl engines. AES (and RSA in latest Via CPUs) is done using an openssl engine which has to be initialised and loaded. This can be done for OpenVPN, Apache, Pound and nearly any other piece of software using OpenSSL, but not OpenSSH. For some reason Theo's people in their infinite wisdom left that part out (it is trivial). There was a patch, dunno if it has made it into the main tree.

As far as non-OpenSSL software is concerned, the kernel itself can use the hardware AES for filesystems and IPSEC. I have run it for quite a while for both OpenVPN and IPSEC. It can run around a Dual Xeon in circles. I would expect it to have the same killer performance for encryption of filesystems and encrypted backups as well. In fact this is possibly the only CPU on the market at the moment where having all of your data encrypted is a realistic proposition. The rest will choke on it and crawl like a 486.

There is also further improvement from having true on-CPU hardware RNG which all programs in need of good random numbers can use as it is implemented at kernel level.

Probably the highest praise to it is the fact that most of these features have now started showing up on Intel roadmap documents for the future x86 CPUs destined for the embedded market. It is the Athlon history repeating. When someone else is doing something right Intel copies it, claims innovation and launches a marketing salvo trying to lie that "they have been doing it all along".

How does it compare?

[Ed Avis]

How does this chip compare in performance per watt against ARM, PowerPC and the like?

The article doesn't say what socket and interface the chip uses. Are they still on Socket 370?

Re:How does it compare?

[pslam]

How does this chip compare in performance per watt against ARM, PowerPC and the like?

Pathetically badly. Most modern low power ARM variants are in the range 0.3-0.5mW/MHz. At 500MHz you'd see them chewing up about 150-250mW. Last I checked the Via x86 chips were single issue, so it's not too unfair to compare an ARM11 (or similar) against them. Quite frankly an ARM11 will outperform the Via chip and run lower power.

The idle power figure is a joke. I can't recall the last time I used an ARM chip that idled at 100mW. More like 1-10mW. Still, it's nice to see an x86 chip get into sub-watt territory.

Of course, ARM doesn't run native x86... and that's pretty much the only reason there's such a large market for these Via x86 chips. It's also the reason you never see them in deeply embedded systems where people don't really care so much about what ISA you're running.

Re:How does it compare?

[dan the person]

I think the popularity is half x86 compatibility(windows users) and half retail cost / availability.

When i was building a linux based PVR, x86 compatibilty was not a deciding factor *. What i wanted was a cheap fanless board that could playback mpeg2 and divx, with a PCI slot for a tuner card, TV-Out, and SATA.

When i was looking there were hundreds of Via C3/C7 based boards from heaps of manufactures, with countless different options. There were one or two ARM and PPC boards, even one with a transmetta CPU, but they didn't have TV-Out, or they had TV-Out but no USB or PCI.

I would have loved to go with another architecture but the market for retail consumers just isn't there.

* Actually, now i've said that i imagine compatibilty of the tuner drivers with non-x86 could be an issue.

Re:How does it compare?

[dreamchaser]

Wow, flashback to the 90's. There is really no such thing as RISC or CISC anymore. Even massive general purpose CPU's like the x86 family use cores that are basically RISC by the classical definition, at least at the microop level. Conversely, today's RISC processors have instruction sets that have grown considerably in complexity since the days of true RISC chips.

Your premise is correct that it is an apples to oranges comparison, but not really for the reasons you describe.

Re:How does it compare?

[Christian Smith]

There is really no such thing as RISC or CISC anymore. Even massive general purpose CPU's like the x86 family use cores that are basically RISC by the classical definition, at least at the microop level. Conversely, today's RISC processors have instruction sets that have grown considerably in complexity since the days of true RISC chips.

RISC is an instruction set thing, with the caveat that RISC instruction sets lend themselves to pipelined instruction execution as a by product.

Yes, modern x86 processors have RISC like microcode implemented using pipelined cores, but the x86 -> microcode converter is extra logic RISC processors just don't need.

There is no way you can implement an x86 chip in the same number of transistors as a RISC chip like ARM or MIPS, hence this VIA chip having considerably more power draw.

Re:How does it compare?

[jimstapleton]

comparing two chips on their power:mhz ratios... Not exactly a good comparison, even within the same general architecture (say both are x86), but when you go cross arch, it gets worse.

Ex. Take an Barton core Athlon and compare it with a 1st Gen P4, running both at the same clock speed. That Barton will significantly outperform the P4, even with the same Mhz. Conversely, thake a Core2 Duo and an Athlon64 X2 of the same clock speed - the Core2 Duo will wipe the floor with the Athlon64 X2.

Mhz only means something when the processors are of the same line. Different lines in an arch can drastically modify the CPUs relative performance by Mhz, varying app to app, and changing the arch completely will destroy most comparisons.

Another example, would be to compare a 500Mhz EV6 Alpha to a 1Ghz Athlon - There are many tasks at which that Alpha will pretty much destroy the Athlon in terms of performance, even at half the clock speed.

So, what you want is power:performance-at-desired-tasks ratios, it's more complex, but it's not useless (and in some cases, counterproductive/counter intuitive)

Re:How does it compare?

[pslam]

I am very much aware that comparing power:mhz is often an incredibly bad thing to do, but I am also very much aware of the internal architecture of these two cores.

• Via is single issue like ARM11. (At least, last I checked, but maybe they've changed that)
• ARM1176 (a common variant) has hit-under-miss caches, some SIMD extensions (slow compared to Via, though), and a decent FPU (optional). No write order dependency issues on ARM. Very comparable to Via.
• ARM11 has much lower memory latency than Via. It only takes 3 clocks to drag something out of memory while execution continues, you get write-to-read forwarding and a lot more registers which means less memory hits overall anyway.
• The bus speeds of both are comparable. External memory is implementation dependent, but can also be matched.

So they're actually pretty similar in a lot of ways. I guess I should restrict my usage of "better" to the usual target market: ARM11 is a better core at being a web browser or general multimedia device. It'll do the same job at lower power. In addition, you could run an ARM11 comfortably past 600MHz without a fan or even a heatsink. If you felt like splashing out, you could get a 4 core variant that would cream pretty much anything Via offers. Obviously 4 times the peak power, but still the amazing idle power consumption most ARMs give you.

Again, x86 is still the obvious choice in the market due to a SOFTWARE problem. I say "problem", but what I really mean is the unwillingness of vendors to write portable code and realise that recompiling for multiple platforms stopped being a major headache about 10 years ago.

It's pretty sad that an ISA is still a barrier to this kind of thing. There is a major example in the volume market where this did work out, though: Apple switching to x86. Hell, they even had to switch endian and everything worked. If anyone ever tells you that switching ISA is prohibitive, go point them at Apple, because it worked out damn well for them, and you can always use Apple as some kind of Godwin's Law because nobody will ever argue they're wrong.

holy cow! and their 1.5GHz is only 7.5W

[spagetti_code]

My mythtv PVR uses the MII12000 (1.2GHz), which is rated at
20-30W. With HDD, DVD, encoder card etc, it draws 80W on start,
and somewhere between 30-60W when running.

Take 10-20W off my figures by using their 1.5GHz ULV
and you get potentially more processing power at less
than 50W!

I know that VIA chips are pretty feeble (i.e. their 1.5GHz
chip is probably closer to a 1GHz intel chip), but with an
encoder card (dual actually) I can be recording two
channels with the CPU at 10%. Given their mobos have
mpeg decoders on board, I can add watching a DVD or TV
for another 30-40% CPU time.

The only thing is ad-skipping and re-encoding are pretty
slow.

Cool!

[Zubinix]

Put this in SBC (Single Board Computer) form together with wireless support and a nice sized flash hard drive would make it ideal for applications such as home monitoring and other uses around the typical house for us home automation geeks.

Redundand?

[spectrokid]

Isn't everybody always complaining how x86 is an awefull archtecture dragging 20 years of backward compatibility like a block of concrete? A one watt processor surely aims at the mobile/embedded market. Backward compatibility is not an issue there. I can't see anybody running his old Windows 3.11 accounting software on his mobile, and this thing won't come with a "Vista-ready" sticker...
Linux and Windows CE (or whatever they call it today) run just fine on ARM and similar. Will a low-power x86 compete performance-wise with a low-power RISK architecture?

I wish mainstream CPUs / GPUs would focus on power

[DrXym]

I wish the EU would start rating PCs by their energy consumption, perhaps accompanied by an energy tax for the worst categories. The amount of power in a modern PC from CPUs & GPUs wasted as heat, fans etc. is just ridiculous.

Re:I wish mainstream CPUs / GPUs would focus on po

[DrXym]

Everyone pays for the power they consume, be it gasoline or electricity. Who cares?

Exactly. Who cares? People are generally selfish and sometimes you must do things that benefit people as a whole instead of individuals. If slapping a tax on the most energy consuming devices in some category causes people to buy the more efficient ones, that is a benefit to every one. If you still want to buy that device despite the tax then nobody is stopping you. But I guarantee that for everyone who does than many more will choose one which doesn't.

It does not mean either that you're getting a crappier machine as a result. While there is a relationship between CPU / GPU performance and power, I doubt it is a 1:1 mapping. Some processors and GPUs are going to deliver more operations per watt than others. Companies and consumers should be encouraged to favour the more efficient designs over the less efficient designs and a tax for the worst offenders in any class is one way of going about that.