Towards the Fanless PC

1. Towards the Fanless PC Bill Gervasi Technology Analyst, Transmeta Chairman, JEDEC Memory Parametrics bilge@transmeta.com

2. The New Multimedia PCs What doesn’t fit? • MP3 music & DVD movies • 100W per channel amplifier • Surround sound speaker system • MP3 music & DVD movies • 100W per channel amplifier • Surround sound speaker system • PC fans, disks, etc. with 75 dB of white noise

3. Market Effects • PC having trouble escaping the den • Too noisy for family room or bedroom • Always-on strategies have failed • Limits applications for PCs • Can’t hook into main sound system • Can’t displace gaming stations • PCs not meeting government standards • Especially in Europe • Too noisy, consume too much power • Office and POS impacted by noise

4. Why Are PCs So Noisy??? Fans everywhere!!! • Fan in the power supply • Fans by the PCI/AGP cards • Fans at the front of the box • Fan on top of the CPU • Fan on top of the graphics controller

6. Know Your Enemy #1 #2 PublicEnemies #3 #4 Wanted: Dead (only)

7. Fan Noise • And these are just the CPU fans!!!

8. Why Do We Need Fans? • CPUs on runaway thermal path • Graphics controller overkill • Memory subsystems not well managed • Add-in cards with unknown wattage requirements

9. First Worst Culprit: The CPU

10. Transistor Trends Pentium is a trademark of Intel Corp.

11. CPU Power Trends

12. CPU Power Density, 2000-2010

13. … and the CPUisn’t the onlypower hog inthe system … … while most subsystems are stable, the graphics controller challenges the CPU for watts …

14. x86 PC Platform Power Graphics

15. PC Graphics • 2D & text essentially unchanged • Addition of video acceleration & data types • 3D explosion • Texturing, bumping • Antialiasing Out of control… !!!

16. PC Graphics Reality • Few features ever used • 2D & text is still the dominant use • Wasted frame buffer performance • 9.6 GB/s memory bandwidth for 2D??? • AGP bus a power drain

17. Memory & Chipsets

18. Memory • Market just now shifting from 3.3V SDRAM • Full size 5 ¼“ DIMMs, 3 slots • Does a mainstream PC need 1.5 GB??? • No power management implemented • Thermal throttles enabled only when the bandwidth is really needed

19. Chipsets • No power management • Inefficient buses with PLLs • “Soft peripherals” using power hungry CPU instead of ultra low power DSPs • Polled mode peripherals burn power on bus • Interrupting protocols (like USB) prevent deep sleep modes

20. What About Other Sources of Noise? • DVD or CD drives • Hard disk drives

21. Other Sources of Noise: DVD Ricoh MP9060A-DP The first thing we didn't like was a noisy work of the optical head (2 times louder than that of TEAC 532EB(32x)). As you know, loud CD spinning is one of the major drawbacks of all CD-ROMs with more than 24x. Here, thanks to the tight-fitting tray, nothing can be heard... but the combine may not "like" some kinds of discs, in this case there begins strong vibration with some noisy effects. … AOpen DRW4624 Noise effects are practically the same as that of the Ricoh device. The construction of the tray's lid is not ideal, so there is some unpleasant air whistle. The combine is not so sensible to the disc quality and balance. It read low-quality discs more quietly and without so strong vibration. The combine did not overheat after it had written 6 discs successively. The tray and the case were just a little warm. Samsung SM-304 In this case noise effects were quite inaudible, the tray fitted tight. The optical head moved noiselessly. The combine is not sensible to the disc quality (perhaps, it depends on the type of the tray). … Toshiba SD-R1002 As for noise effects we can place this combine between Ricoh and Samsung. Since there installed the standard tray, you can hear the "standard" air noise. The combine is not very sensitive to the disc quality, though there is some light vibration. The tray's lid fits quite tight. The optical head moves noiselessly. … Source: http://www.digit-life.com/articles/dvdcdrwreview/

22. Other Sources of Noise: HDD db(A)

23. What effecthas this trend hadon the PC market?

24. Desktop PCs are a Commodity • Margins are shrinking everywhere so OEMs are relying upon other sources • Internet signup bounties (AOL, Earthlink) • Subscription services (Real Networks) • Software services (Quicken) • Press & Analysts are saying the “PC is dead” • Rapid technology advances have out-paced user needs • Free CPU Cycles, Free GB, Free Bandwidth

25. What the world needs now…efficient computingecoPC

26. ecoPC Goals • No fans, no noise • Never needs to beturned off • Utilize existing industry infrastructure • Lay out a new roadmap for the future • Cost competitive with BYO generic boxes

27. Today’s Product Differentiation iPAQ Desktop DISCOVERY Thin Client NetVista iMac Differentiated designs – right idea but NO MASS MARKET Prevents volume discount of infrastructure

28. What Do BYO Generic Boxes Do Right? $BOM $BOM $BOM These things are dirt cheap because they use standard parts

29. ecoPC: Segment DefinitionWindows XP Based PC • Low Energy Consumption  15Watt Typical, 20Watt Max • Low Cost of Acquisition  Sub $800 • Low Noise  No fans, quiet drives = Silent PC • Low Space Consumption  1” thick chassis • Low Cost of Operation  Low Energy Bills from Power Efficiency • Low TCO Maintenance Costs  Legacy Free • Low Cost of Manufacturing & Assembly  Standard parts like BYO generic

30. ecoPC -- Key Specs Similar to today’s notebooks • Low power x86 CPU & energy efficient chipset • Low power graphics, integrated or discrete • Low power hard disk & optical drive • RAM: DDR 2.5V • External power supply • No cooling fans • Legacy free • USB or Bluetooth keyboard & mouse • Integrated LAN, modem, 802.11 wireless

31. ecoPC -- Expansion • No extra bays; only external expansion • Universal Flash slot: CF, Smart, Stick • No PCI-class add-in slots • Cardbus? Possibly…need a better expansion strategy! • 1394 & USB suffer from abstraction overhead • Universal Docking with serialized host bus • PCI or HyperTransport or 3GIO • Merges out-of-box with native contact

32. ecoPC Peripherals • New ecoPC specification needed • Acoustic limits defined • Drives selected for low noise • DVD • Hard disk • Power limits strictly enforced • Thermal/power sensors prevent violation • ecoPC certification and logo

33. ecoPC Processing Units On Demand processing • Monitor system activity and shut off unused execution units • Scale operational frequency on application demand • E.g., LongRunTM & PowerNow!TM • Utilize every microsecond that power is being burned • Offload interruptions to remote low power units (e.g., DMA units, DSPs) LongRun is a trademark of Transmeta Corp.PowerNow! is a trademark of AMD Corp.

34. Power = CV2f% Keys to mobile design: • Reduce C and V • Match f to demand • Minimize duty cycle • Utilize power states Factors: • Capacitance (C) • Voltage (V) • Frequency (f) • Duty cycle (%) • Power states

35. ecoPC CPU • Low Transistor Count CPU • Seldom executed instructions in software • Run time optimization • Scaleable operating frequency and voltage • Integrates smart memory controller • Utilize every powered microsecond

36. ecoPC Graphics • Shuts down unused pipes • 2D, 3D, video • Rendering engines • Slows memory during screen refresh • Avoid unnecessary operations • Scatter-gather DMA using SMA • Focal point prioritized rendering resolution • Thermal limits switch rendering style • Reduce rendering quality of low priority objects

37. ecoPC Memory SDR  DDR I DDR II • JEDEC roadmap triples GB/s/W with each generation • Power reduction of 30% • Bandwidth doubles • Move from 3 DIMMs to 2 SO-DIMMs • Sufficient capacity, higher performance, lower power, and no evil PLLs 3.3V  2.5V  1.8V

38. Power: DDR II vs DDR I vs SDR Four times the bandwidth yet half the power! DDR533 “DDR II” DDR333 “DDR I” PC133

39. Low Power DRAM Futures • Aggressive use of power states (CKE) • Increased refresh flexibility • Temperature compensated refresh • Partial array refresh • Reduced page size • Fewer cells discharged/recharged

40. ecoPC DRAM Timing Relaxed mode timing • Comprehend effects of DLL • Aligns data to clock on reads… only! • Use DRAM in low performance mode while DLL is not locked • Accommodate wide range on clock to strobe CK DQS >  tDQSCK

41. Strobe to Data is Fixed DQS  tDQSQ even odd ODDDATA DLL has no effect on data to strobe timing, therefore DRAM can be used while DLL not locked! L ODDDATAENABLE 8 EVENDATA DATA H DQS EVENDATAENABLE

42. Why Relaxed Mode Timing? Utilize the DLL/PLL lock times • 2-100 ms per power management event • Allows much finer granularity on control • Better utilization of powered on state • Switch back to full performance mode after the DLL/PLL lock • This concept can be applied to any locked bus

43. BuildingtheecoPC

44. Today’s PC

45. Cooler CPU

46. Integrated Graphics

47. Efficient Memory

48. Eliminate PCI

49. No Fans

50. Slimline Case