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bitL

Pros:

- 64GB for desktop (finally!)

- 26 PCIe lanes (i.e. multiple fast M.2 PCIe NVMe, making 5k/4k RAW video previewing possible in real-time)

OK:

- very small performance increase comparing to Haswell two generations ago (Broadwell?)

- DDR4 performance matches XMP DDR3 performance; to see any difference you need to use quad channel configuration

- SGX, the jury is out on this one (double-edged sword, could improve security but also turn into a complete malware mess due to enclave isolation and inability to detect running encrypted botnets once they gain ring 0)

Cons:

- power consumption is up (!?)

- no AVX-512 for desktop

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SGX is terrifying. Botnets are not the main problem. Windows (N+1) using SGX to make it hard/impossible to remove the spyware (and other junk)[1] is the problem. As an example, take a "trusted" environment[2] and add SGX as a way of keeping end users out of the TEE.

While it is still early, SGX may be a key battlefield in the War On General Purpose Computing.

[1] e.g. the stuff discussed recently https://news.ycombinator.com/item?id=9976298

[2] http://i.imgur.com/rjbzWyB.jpg

Very terrifying indeed. IMHO these days there is far too much freedom being traded away for security, and users are gradually conditioned toward it. The thinking is almost like "How about we put everyone in prison, because some percentage of them will become criminals anyway?"

Back then it was relatively easy to patch your OS --- even if it was proprietary and closed-source --- to make it behave how you wanted to, if you knew what to change (see all the Windows customising forums for an example, and the whole cracking community.) You didn't have to give up proprietary software completely and move to something like Linux. Now it's become much harder, and I feel that the middle ground between fully open-source and fully closed has mostly disappeared as the two communities are gradually distancing from each other.

http://www.gnu.org/philosophy/right-to-read.en.html

The ability to use a General Purpose Computer and an IP address (non-NAT!) gives anybody the ability to publish without any gateway or authority being able to control what can be published. This is real power, in the long-term.

It is logical that the people who traditionally hold the power of what information can be published to large audiences - that is, the people that used to control the scarce resources that limited publication - would really like to see all these troubling technologies stuffed back into Pandora's Box and locked away behind the traditional gatekeepers where they won't cause trouble.

It's called the Digital Imprimatur[1], and it has been implemented while everybody else was busy distracted by technical minutia and dreams of stock options. Locking down "true"-root access with SGX (or other hardware tricks like SecureBoot) is one of the last steps. If we fail fight this trend right now... well... what good is a compiler when you can't trust[2] the environment it is running in?

[1] https://www.fourmilab.ch/documents/digital-imprimatur/

[2] (pdf) https://www.ece.cmu.edu/~ganger/712.fall02/papers/p761-thomp...

It's "terrifying" but it's also something that's often desired. For example, SGX could enable things like a trusted Bitcoin mixer. Or a trusted telephony provider. Remote code trusting is pretty cool for such scenarios where the other option is "well, sure, you gotta trust the site, but...".

The downside is that it'll be too juicy for DRM and games to pass up, and that's shitty and most likely outweighs the benefit. Perhaps if Intel had limited SGX to server workloads and gave us AVX512 instead.

(I'm guessing on SGX here. I am unaware of any detailed info on how exactly it'll work, how the remote attestation works.)

Lots of info here: http://sgxisca.weebly.com/ Not a whole lot on remote attestation though

Thanks, that looks very useful!

why do you need Bitcoin if you can trust the remote code? ;)

Is Doctorow's 28c3 keynote so well known, that a link is not necessary anymore?

http://boingboing.net/2011/12/27/the-coming-war-on-general-p...

The problem that you describe is not an SGX problem, it is an OS trust problem. The current trust model for general purpose computing is such that a processor is not in a position to prevent a malicious OS from controlling which applications run, whether that processor supports SGX or not. The malicious OS may of course use SGX if it wants to ensure that unprivileged code has not been tampered with, but do not equate tamper proofing with keeping end users out. SGX does not strengthen a malicious OS at the expense of user software. On the contrary, it provides computing services directly to an application, removing supervisor code from the TCB of the application. That having been said, I agree that any move to keep users out of their own systems is troubling and that users should be cautious and not take security and trust claims at face value.

TDP is up. Power consumption is down. TDP is only a maximum value, and due to Skylake's increased power density, it doesn't correlate 1:1 with power consumption.

I would also like to add that they killed the EHCI controller, making installing Win7 more difficult. Also, TSX is back of course.

I don't know much about this but, regarding DD4, the article says on page 7: "upgrading to DDR4 doesn’t degrade performance from your high end DRAM kit, and you get the added benefit of future upgrades, faster speeds, lower power consumption due to the lower voltage and higher density modules."

So maybe it balances out the power consumption?

> M.2

My impression was that M.2 is going out of style, at least for desktop - the primary form factor for the Intel 750 etc is an actual PCIe card. The alternative connector if you want a 2.5" drive form factor is U.2 (SFF-8639).

The Intel 750 is officially speaking a consumer product, but it's pretty out there. M.2 is far more popular and is doing a pretty good job of supplanting mSATA and effectively prevented SATA Express from being adopted. U.2 is brand new and is only going to show up on the most expensive consumer products, but M.2 can be found on a lot of motherboards under $100.

You're right, it looks like most of the Skylake launch boards in Anandtech's review are M.2. Somewhat disappointing. I still suspect M.2 is obsolete in the long run, but seemingly not for this generation of Skylake.

There are at least a couple boards I see with a dedicated PCIE 3.0 x4 slot and U.2 support, but they're the highest end and I'm sure not cheap.

You can connect a 2.5" U.2 drive (Intel 750) to M.2, but it's obviously going to reduce performance to M.2 speeds.

M.2 supports the same performance as U.2. Both connectors allow for up to 4 lanes of PCIe. Some lower-cost implementations of M.2 only provide 2 lanes, and it also can provide SATA signals instead of PCIe, but with Intel's desktop chipsets finally getting a bandwidth upgrade everybody is going to be implementing M.2 with four lanes going forward.

Ah, I guess I'm used to the Haswell DMI bus speed still, which severely limited M.2 speed even if it was 3.0 and 4 lanes. I guess that's probably not the case with Skylake.

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