Team 4 Project 2 Presentation Flat Panel Displays, Serial ATA, & SCSI Tom, Jen, Curtis, Ashley, Scott

Flat Panel Display Types  Liquid Crystal Display (LCD)  Static  Advantages:  Compact and Light  Lower power consumption  Not affected by screen burn in  Disadvantages:  Limited viewing angle  Bleeding or uneven backlighting  One native resolution  Dead or stuck pixels

Flat Panel Display Types  Plasma  Volatile  Advantages:  Picture quality  Less visible motion blur  Higher refresh rates and faster response times  Disadvantages:  Screen burn in  Uses more electricity than LCD  Do not work at high altitudes

What is SCSI?  SCSI is a set of standards for physically connecting and transferring data between computers and peripheral devices.  Originally stood for Small Computer System Interface  SCSI goes back to 1979  A SCSI Host can control up to either 8 or 16 devices

SCSI TYPES  SCSI-1: The original specification developed in 1986, SCSI-1 is now obsolete. It featured a bus width of 8 bits and clock speed of 5 MHz.  SCSI-2: Became the standard in 1994  Included the Common Command Set (CCS) commands considered an absolute necessity for support of any SCSI device.  Double the clock speed to 10 MHz (Fast),  Double the bus width from to 16 bits and increase the number of devices to 15 (Wide),  or double both (Fast/Wide).  SCSI-2 also added command queuing, allowing devices to store and prioritize commands from the host computer.  SCSI-3: showed up in 1995 and included a series of smaller standards within its overall scope.  Most SCSI-3 specifications begin with the term Ultra, such as Ultra for SPI variations, Ultra2 for SPI-2 variations and Ultra3 for SPI-3 variations.  SCSI-3 is the standard currently in use.

SCSI Advantages  Can support up to 7 drives on a narrow bus or 15 on wide bus inside or outside the box  SCSI allows for queuing to each device  SCSI uses 5% of CPU whereas IDE uses 95%

What is Serial ATA?  Serial ATA (Serial Advanced Technology Attachment)  New interface for high volume storage drives and disks  Communicates using a single high-speed 7 wire serial cable

SATA Advantages  Physically smaller and more efficient  Faster than previous generations  Less cables  Doesn’t use jumpers (no master/slave)  Point to point topology

Possible Failures  Hard drives (SCSI & SATA) Failures  Defective drives  Mechanical  Motor  Spindles  Read write heads  Power cables are not seated properly  Out-of-Date BIOS

Failure Rates – Hard Drives  Failure  “a drive is considered to have failed if it was replaced as part of a repairs procedure”  Roughly 5 years  No set timeframe for failures  Annual replacement rate:  1%  2-4%  13%

Failure Rates – Hard Drives  S.M.A.R.T.  “Self Monitoring And Reporting Technology”  Warn user of impending hard drive failure  Gives user time to  Back-up/copy data  Find suitable replacement

Failure Rates – Hard Drives  Points of failure  60% mechanical  Motors  Spindles  Read/Write Heads

Failure Rates – Hard Drives  Causes  Dust  Smoke  Amount of Use  Temperature has little to no effect on drive reliability  15-60% of returned drives were deemed to have to defect  No discernible difference between FC, SCSI, SATA

Possible Failures  SCSI:  LUN (address)  Termination  Flat Panel Displays:  Dead pixels  Striping  Poor quality  Blank screen

Questions?  T/F - LCD stands for Light Crystal Display.  T/F - SCSI stands for Small Computer System Interface.  Name a disadvantage of LCD.  What percentage of the CPU does SCSI use?  Which flat panel device does not work at high altitudes?