Silvermont Explained

Silvermont
Produced-Start:From 2013
Manuf1:Intel
Cores:2–8
Size-From:22 nm
Instructions:x86-16, IA-32, x86-64
Extensions:MMX, SSE, SSE2, SSE3, SSSE3, SSE4, SSE4.1, SSE4.2
Extensions1:AES-NI, RDRAND, CLMUL
Extensions2:VT-x
Predecessor:Bonnell
Saltwell
Successor:Airmont (die shrink),
Goldmont (new microarchitecture)
Brand1:Atom
Brand2:Celeron
Brand3:Pentium

Silvermont is a microarchitecture for low-power Atom, Celeron and Pentium branded processors used in systems on a chip (SoCs) made by Intel. Silvermont forms the basis for a total of four SoC families:[1]

Silvermont is the successor of the Bonnell, using a newer 22 nm process (previously introduced with Ivy Bridge) and a new microarchitecture, replacing Hyper Threading with out-of-order execution.[2]

Silvermont was announced to news media on May 6, 2013, at Intel's headquarters at Santa Clara, California.[3] Intel had repeatedly said the first Bay Trail devices would be available during the Holiday 2013 timeframe, while leaked slides showed that the release window for Bay Trail-T as August 28 – September 13, 2013.[4] Both Avoton and Rangeley were announced as being available in the second half of 2013. The first Merrifield devices were announced in 1H14.[5]

According to the Tick–tock model Airmont is the 14 nm die shrink of Silvermont, launched in early 2015 and first seen in the Atom x7-Z8700 as used in the Microsoft Surface 3.[6] Airmont microarchitecture includes the following SoC families:[7]

Silvermont based cores have also been used, modified, in the Knight's Landing iteration of Intel's Xeon Phi HPC chips.

Design

Silvermont was the first Atom processor to feature an out-of-order architecture.[8]

Technology

See also: Intel Graphics Technology.

Errata

Intel revealed in its Q4 2016 quarterly report that there were quality issues in the C2000 product family, which had an effect on the financial performance of the company's Data Center Group that quarter.[12] An erratum named AVR54 published by Intel; state there is a defect in the chip's LPC clock, and affected systems "may experience inability to boot or may cease operation".[13] [14] [15] A workaround is available requiring platform hardware changes. The SoC failures are thought to have led to failures in Cisco and Synology products,[16] though discussion of the C2000 as the root cause of failure has been reported to be under a non-disclosure agreement for many vendors.[17]

Intel released a new C0 stepping of the C2000 series in April 2017 which corrected the bug.[18]

In July 2017 Intel published that a similar quality issue affects also Atom E3800 series embedded processors. The erratum named VLI89 published by Intel state, similar to issue with Atom C2000, that there is a defect in the chip's LPC clock and affected systems "may experience inability to boot or may cease operation".[19] Issues extend also to USB bus and SD card circuitry and should happen "under certain conditions where activity is high for several years". In April 2018 Intel announced it is releasing a new D1 stepping to fix the issue.[20]

The LPC, USB and SD Card buses circuitry degradation issues also apply to other Bay Trail processors such as Intel Celeron J1900 and N2800/N2900 series;[21] also to Pentium N3500, J2850, J2900 series; and Celeron J1800 and J1750 series—as those are based on the same affected silicon.

Cisco stated failures of Atom C2000 processors can occur as early as 18 months of use with higher failure rates occurring after 36 months.[22]

Mitigations were found to limit impact on systems. Firmware update for the LPC bus called LPC_CLKRUN# reduces the utilization of the LPC interface what in turn decreases (but not eliminates) LPC bus degradation - some systems are however not compatible with this new firmware. USB should have a maximum of 10% active time and there is a 50TB transmit traffic life expectancy over the lifetime of the port. It is recommended not to use SD card as a boot device and to remove the card from the system when not in use.

Bay Trail issues on Linux

It has been widely reported that Bay Trail CPUs (and possibly their derivatives including Airmont/Braswell/Cherry Trail) experience random freezes / lock-ups on various Linux kernels. Reference Linux bug report 109051 on Kernel.org Bugzilla, first reported Dec-2015. Workaround seems to be setting the Linux kernel flag intel_idle.max_cstate=1, which while eliminating the system freezes/lock-ups, results in increased CPU power/battery usage by preventing the CPU from entering higher power-saving C-states. Systems running Windows-OSes apparently do not experience these lockup/freeze issues.

Bay Trail issues on FreeBSD

A potential fix is to set and via .

Airmont issues

14 nm Airmont architecture processors are also affected by the design flaws as noted in the Braswell Specification Update under CHP49 errata.[23] In addition to LPC and SD Card circuitry degradation issues those 14 nm designs also have issues with Real Time Clock (RTC) circuitry degradation, their USB buses are however not affected. Unspecified firmware changes are required to mitigate RTC circuitry degradation. Intel does not plan to release a new stepping for Braswell. Intel admitted the issue stating the impact on consumers depends on use condition.[24]

List of Silvermont processors

Desktop processors (Bay Trail-D)

List of desktop processors as follows:

Target
segment
Cores
(threads)
Processor
branding and model
GPU modelTDPTurbo
(GHz)
GPU freq.
(MHz)
L2
cache
(MB)
Release
date
Price
(USD)
1-coreBaseTurbo
Value4 (4)PentiumJ2900HD Graphics
(4 EU)
10 W / 2.41 GHz2.676888962Q4 2013$94
J2850792Q3 2013
CeleronJ190010 W / 2.0 GHz2.42854Q4 2013$82
J1850792Q3 2013
2 (2)J180010 W / 2.41 GHz2.581Q4 2013$72
J1750750Q3 2013

Server processors (Avoton)

It has been found that a bug in the blueprint of the C2000 CPUs family may cause failure of its embedded Ethernet ports.

List of server processors as follows:[25]

Target
segment
Cores
(threads)
Processor
branding and model
GPU modelTDPCPU
Turbo
(GHz)
Graphics clock rateL2
cache
(MB)
Release
date
Price
(USD)
1-coreNormalTurbo
Server8 (8)AtomC275020 W / 2.4 GHz2.64Q3 2013$171
C27302.0$150
 4 (4)C25502.62$86
C25302.0$70
 2 (2)C23501$43

Communications processors (Rangeley)

List of communications processors as follows:[26]

Target
segment
Cores
(threads)
Processor
branding and model
GPU modelTDPCPU Turbo
(GHz)
GPU freq.Intel
QuickAssist
L2
cache
(MB)
Release
date
Price
(USD)
1-coreNormalTurbo
Communications8 (8)AtomC275820 W / 2.4 GHzYes4Q3 2013$208
C2738No
C271818 W / 2.0 GHzYes$182
4 (4)C255815 W / 2.4 GHz2$104
C2538No
C251813 W / 1.7 GHzYes$91
C25089.5 W / 1.25 GHzQ2 2014$98
2 (2)C23587 W / 1.7 GHz2.01Q3 2013$60
C2338No
C23086 W / 1.25 GHzYesQ2 2014

Embedded/automotive processors (Bay Trail-I)

List of embedded processors as follows:[27]

Target
segment
Cores
(threads)
Processor
branding and model
GPU modelTDPCPU TurboGPU freq.
(MHz)
L2
cache
Release
date
Price
(USD)
1-coreBaseTurbo
Embedded4 (4)AtomE3845HD Graphics
(4 EU)
10 W / 1.91 GHz5427922 MBQ4 2013$52
 2 (2)E38278 W / 1.75 GHz1 MB$41
E38267 W / 1.46 GHz533677$37
E38256 W / 1.33 GHz$34
 1 (1)E38155 W / 1.46 GHz400512 KB$31
 2 (2)E38053 W / 1.33 GHz1 MBQ4 2014

Mobile processors (Bay Trail-M)

List of mobile processors as follows:

Target
segment
Cores
(threads)
Processor
branding & model
GPU modelTDPCPU
turbo
(GHz)
GPU freq.
(MHz)
L2
cache
(MB)
Release
date
Price
(USD)
BaseTurbo
Value 4 (4)PentiumN3540Intel HD Graphics
(4 EU)
7.5 W / 2.16 GHz2.6631389622014-07-20$161
N35302.582014-02-23
N35207.5 W / 2.166 GHz2.428542013-11-03
N35107.5 W / 2.0 GHz7502013-09-11
CeleronN29407.5 W / 1.83 GHz2.25854Q3 2014$107
N29302.162014-02-23
N29207.5 W / 1.86 GHz2.08442013-11-03
N29107.5 W / 1.6 GHz7562013-09-11
 2 (2)N28407.5 W / 2.16 GHz2.583117921Q3 2014
N28302.413137502014-02-23
N28207.5 W / 2.13 GHz2.397562013-11-03
N28157.5 W / 1.86 GHz2.13
N28107.5 W / 2.0 GHz2013-09-11
N28084.5 W / 1.58 GHz2.25311792Q3 2014
N28074.3 W / 1.58 GHz2.163137502014-02-23
N28064.5 W / 1.6 GHz2.07562013-11-03
N28054.3 W / 1.46 GHz6672013-09-11

Tablet processors (Bay Trail-T)

List of tablet and hybrid processors as follows:

Target
segment
Cores
(threads)
Processor
branding & model
SDP[28] (W)CPU freq.
(GHz)
L2
cache
(MB)
GPU modelGPU freq.
(MHz)
MemoryMax display resolutionSocketRelease
date
Price
(USD)
BaseTurboBaseBurstType
  1. channels
Max speedMax bandwidthMax supported
Value4 (4)AtomZ379521.662.392HD Graphics (4 EU)311778LPDDR32x64b1067MT/s17.1 GB/s4 GBFCBGA1380Q1 2014$40.00
Z37852.21.492.413138331333MT/s21.3 GB/sQ2 2014
Z377521.462.393117781067MT/s17.1 GB/sQ1 2014$35.00
Z3775D2.21.492.41792DDR3L-RS1x64b1333MT/s10.6 GB/sQ1 2014$35.00
Z377021.462.39667LPDDR32x64b1067MT/s17.1 GB/s2560×160011 September 2013$37.00
Z3770D2.21.52.41313688DDR3L-RS1x64b1333MT/s10.6 GB/s2 GB1920×1280
Z374021.331.86311667LPDDR32x64b1067MT/s17.1 GB/s4 GB2560×1600$32.00
Z3740D2.21.83313688DDR3L-RS1x64b1333MT/s10.6 GB/s2 GB1920×1280
Z3735F31164610.6 GB/s1920×1200FCBGA592Q1 2014$17.00
Z3735G1x32b5.3 GB/s1 GB1200×800
 2 (2)Z36802.01667LPDDR31x64b1067MT/s8.5 GB/s1280×80011 September 2013rowspan="2"
Z3680D688DDR3L-RS1x64b1333MT/s10.6 GB/s2 GB1920×1280

Smartphone processors (Merrifield)

List of smartphone processors as follows:

Smartphone processors (Moorefield)

List of smartphone processors as follows:

List of Airmont processors

Desktop processors (Braswell)

List of desktop processors as follows:

Target
segment
Cores
(threads)
Processor
branding and model
GPU modelTDPTurbo
(GHz)
GPU freq.
(MHz)
L2
cache
(MB)
Release
date
Price
(USD)
Brand name &<br/>model numberEU1-coreBaseTurbo
Desktop4 (4)PentiumJ3710HD Graphics 405186.5 W /
1.6 GHz
2.644007402January
2016
N/A
CeleronJ3160HD Graphics 400126 W /
1.6 GHz
2.24320700
2 (2)J30602.482
[29]

Mobile processors (Braswell)

List of mobile processors as follows:

Target
segment
Cores
(threads)
Processor
branding and model
GPU ModelTDPTurbo
(GHz)
GPU freq.
(MHz)
L2
cache
(MB)
Release
date
Price
(USD)
Brand name &<br/>model numberEU1-coreBaseTurbo
Mobile4 (4)PentiumN3710HD Graphics 405166W /
1.6 GHz
2.564007002Q1 2016$161
N3700HD Graphics (Braswell)[30] 2.4Q1 2015
CeleronN3160HD Graphics 400122.24320640Q1 2016$107
N3150HD Graphics (Braswell)
2.08Q1 2015
2 (2)N3060HD Graphics 4002.486002Q1 2016
N3050HD Graphics (Braswell)
2.16Q1 2015
N3010HD Graphics 4004W / 1.04 GHz2.24Q1 2016
N3000HD Graphics (Braswell)
2.08Q1 2015

Tablet processors

(Cherry Trail)

List of smartphone and tablet processors as follows:

Target
segment
Cores
(threads)
Processor
branding and model
SDP
(W)
L2
cache
(MB)
CPU freq.
(GHz)
GPUSocketRelease
date
Price
(USD)
Brand nameEUFreq. (MHz)
BaseTurbo 1-coreBaseTurbo
Tablet4 (4)Atom x7Z8750221.62.56HD Graphics16200600FCBGA1380Q1 2016$37
Z87002.4Q1 2015
Atom x5Z85501.4412$27
Z85002.24
Z83501.92500FCBGA594Q1 2016$21
Z8330
Z83001.84Q2 2015$21

Other uses

Silvermont based processor cores have been used in Knights Landing versions of Intel's Xeon Phi multiprocessor HPC chips, with changes for HPC including AVX-512 vector units.

See also

Notes and References

  1. Web site: Intel Launches Low-Power, High-Performance Silvermont Microarchitecture . Intel.com . 2013-05-06.
  2. Web site: Deep inside Intel's new ARM killer: Silvermont . The Register . 2013-05-08 . 2014-04-08.
  3. Web site: Intel Launches Low-Power, High-Performance Silvermont Microarchitecture . Newsroom.intel.com . 2013-05-06 . 2014-04-08.
  4. Web site: Intel Bay Trial-T launches August 28 – September 13 . guru3d.com . 2013-07-04.
  5. Web site: Intel reveals Merrifield processor . engadget.com . 2013-06-04.
  6. Web site: Intel quietly launches 14nm Braswell, Bay Trail's successor. ExtremeTech. Joel Hruska. March 31, 2015.
  7. Web site: Michael Kan . Intel plans new 'Braswell' chip for PCs, over 20 Chromebooks . PCWorld . 2014-04-08.
  8. Web site: Intel's Silvermont Architecture Revealed: Getting Serious About Mobile. Anand Lal Shimpi.
  9. Web site: Download Intel® Graphics Driver for Windows 7* and 8.1*, and Windows® 10 [15.33]]. Drivers & Software.
  10. Web site: Intel HD Graphics Drivers v10.18.10.3621 with one new OpenGL Extension . Geeks3D . 2014-06-05.
  11. Web site: OpenGL ES Conformant product list. 11 January 2014. Khronos Group. 11 January 2014.
  12. News: Alcorn. Paul. CPU Failures Hurt Intel's Bottom Line. 7 February 2017. Tom's Hardware. 31 January 2017.
  13. News: Hellstrom. Jeremy. Intel's Atom C2xxx processors may just make like a banana and split. 7 February 2017. PC Perspective. 7 February 2017.
  14. News: Calburn. Thomas. Atom C2000 chips are bricking products – and it's not just Cisco hit. 7 February 2017. The Register. 6 February 2017.
  15. Web site: Intel Atom Processor C2000 Product Family Specification Update. Intel Atom Processor C2000 Product Family Specification Update. Intel. 7 February 2017.
  16. News: Kampman. Jeff. Report: Some embedded Atom CPUs can brick their host systems. 7 February 2017. Tech Report. 7 February 2017.
  17. News: Kennedy. Patrick. The Intel Atom C2000 Series Bug – Why It is So Quiet. 28 February 2017. ServeTheHome. 7 February 2017.
  18. News: Robinson. Cliff. Intel Atom C2000 C0 Stepping Fixing the AVR54 Bug. 25 April 2017. Serve the Home. 23 April 2017.
  19. Web site: Intel Atom® Processor E3800 Specification Update. 2018-04-13.
  20. Web site: Product Change Notification 116196 - 00. 2018-04-09.
  21. Web site: Intel® Celeron® Processor J1900, N2807 & N2930 for Internet of Things Platforms Specification Update Addendum. 2018-04-14.
  22. Web site: Clock Signal Component Issue. Cisco. 2018-04-14.
  23. Web site: N-series Intel® Pentium® Processors and Intel® Celeron® Processors Specification Update. 2018-04-15.
  24. Web site: Another Atom Bomb Intel Atom E3800 Bay Trail VLI89 Bug. 2018-04-13. ServeTheHome.
  25. Web site: Intel® Atom™ Processor for Server . Ark.intel.com . 2014-04-08.
  26. Web site: Intel® Atom™ Processor for Communications . Ark.intel.com . 2014-04-08.
  27. Web site: Products (Formerly Bay Trail) . Ark.intel.com . 2014-04-08.
  28. Web site: Intel® Atom™ Processor Z36xxx and Z37xxx Series: Datasheet, V.1 . Intel.com . 2014-04-08.
  29. Some initial reports stated that the processor has 1 MB L2 cache; see Web site: Notes below Specifications. Anthony Shvets. CPU World.
  30. Web site: Intel HD Graphics (Braswell). Klaus Hinum. January 26, 2016. Notebookcheck Publishing GmbH.