ThinkWiki - User contributions [en]

Problem with Pixel Error

2008-08-08T00:43:36Z

Hkazemi: /* Solutions */ PixChanger links updated

This page provides information about pixel and subpixel errors.

==What are dead pixels or dead subpixels?==
Dead Pixels are a phenomenon caused by the technology of LCD displays. TFT displays consist of a huge number of individual display cells, each controlled by its own transistor. I.E. a display with a resolution of 1024x768 pixels consists of 1024x768x3 = 2,36 million cells. A such enormous number makes the production of a display without any faulty cell difficult. The more strict the quality restrictions are, the more expensive the panels get, because this simply means raising the number of garbage panels.

==Types of pixel errors==
Here is a listing of possible types of dead pixels / subpixels:
{| cellspacing=0 cellpadding=2 border=1 style="text-align:center"
! pixel type<hr />state type !! pixel !! red subpixel !! green subpixel !! blue subpixel
|-
| always lit ||   ·   ||   ·   ||   ·   ||   ·  
|-
| always unlit ||   ·   ||   ·     ·   ||   ·     ·   ||   ·     ·  
|}

You can notice here, that always lit complete pixels, red subpixels and green subpixels are the most annoying ones. Also, dead pixels located closer to the center of the screen are more annoying than such located closer to the edge of the screen.

Dead pixels do not always have to be a constant phenomena. You might in fact experience your pixel in question be faulty at times and working perfectly at other times. Or you might experience it to be a little flickering. This is only logical since a faulty transistor might sometimes work and sometimes not, depending on environmental conditions or even just randomly.

{{HINT|The table above also shows you a way of detecting dead pixels and subpixels. Just use plain colored screens.}}

==The ISO 13406-2 norm==
However, to give the concerned customer more transparency when buying LCD displays, the ISO norm 13406-2 was introduced, providing a basis for warranty claims. By assuring one of the classes of this specification, the producer is bound to keep that quality standard throughout the whole production series. However, Manufacturers are not necessarily going with this standard. For values for IBM displays look at [http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-4U9P53 this page].

The values in the following table state the acceptable errors per 1 million pixels. Dead pixels form a cluster when they are within a square of 5x5 pixels.

{| cellspacing=0 cellpadding=2 border=1 style="text-align:center"
! Error class !! Type 1 (always lit pixel) !! Type 2 (always unlit pixel) !! Type 3 (always lit or always unlit subpixel) !! Type 4 (clusters with more than one Type 1 or Type 3 faults) !! Type 4 (clusters of Type 3 faults)
|-
| I || 0 || 0 || 0 || 0 || 0
|-
| II || 2 || 2 || 5 || 0 || 2
|-
| III || 5 || 15 || 50 || 0 || 5
|-
| IV || 50 || 150 || 500 || 5 || 50
|}

==Causes for dead pixels/subpixels==
* As stated above, dead pixels are an inherent feature of the technology/production process of TFT displays. How many of them are in the final displays sold is just a matter of quality control standards.
* Furthermore, they can also accur at random time after production. Transistors can have faults that are not recognizable at production time. These faults may make the transistor stop working after it has been in use for a certain amount of time.
* Mechanical or environmental stress (i.e. heat) can possibly damage a transistor, leading to pixel errors.

==Don't panic!==
Dead pixels are a really common phenomena on TFT displays. In fact there are other things about TFT displays that matter a lot more, like brightness and contrast, picture stability, color reproduction and response time. People just tend to focus on those things that are the most obvious, that's why everyone cries for dead pixels and response time when it comes to TFT displays.

However, as stated above there can be truely annoying types of dead pixels. If their count is higher than the displays quality class permits you might get the device replaced under warranty.
The best thing, however, is to look for dead pixels right after purchase (you might have a chance to return it without special reason then):
* Do it three times over two days - different moods and different environemental light have an influence on your perception.
* [http://freshmeat.net/projects/lcdtest lcdtest] utility can generate predefined patterns, and may help you to detect damaged pixels.
* Be concious about how hard it was to find the dead pixel - if it was really hard it can't be too bothering.
* Also make sure that what you consider a dead pixel isn't just a piece of dirt or dust.
* Try pressing the (blue) scroll button on the UltraNav. There is a bug in the UltraNav driver which causes fake Bright pixels to appear on the screen, especially if FireFox is used as browser. See [[UltraNav]] for more information

==Solutions==
Besides some april jokes there isn't really any solution except looking for a replacement.

However, for {{Windows}} an interesting program exists that can help you making annoying subpixels and pixels more bearable. It works by trying to compensate a dead subpixel by adjusting the values for the remaining working subpixels. This way you can i.e. get rid of a most annoying always lit red subpixel. It is called PixChanger and was written by Daniel Goebel and Denny Koberling. Although it is only available in German, it works fine on English versions of Windows XP and is relatively easy for English speakers to figure out:
*Version 1 download and discussion: http://www.prad.de/board/thread.php?threadid=11797
*Version 2 download: http://www.pixchanger.de.vu/
*Discussion: http://www.forum-3dcenter.org/vbulletin/showthread.php?s=&threadid=152832&perpage=20&pagenumber=1
*Discussion and screenshots: http://www.forum-3dcenter.org/vbulletin/showthread.php?t=152832&pp=20&page=6

If you have a '''line''' of dead (bright or dark) pixels, this is usually caused by a failure of one of the address-lines where it contacts the edge of the panel. You can sometimes restore it by (''carefully''!!) flexing the display. Find the point on the bezel where the line ends, then push it gently with a thumb (or from behind) while supporting the outer edges of the display with 2 fingers. The LCD needs to be
"folded" by about 1 degree; the fold direction depends on the problem. I can report success with an X20. Note that this is a last resort; it '''might destroy your LCD''', and the LCD should thereafter be treated exceptionally gently!

==External sources==
* [http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-4U9P53 IBMs page on defective pixel display replacement criteria]
* [http://www.tomshardware.com/2003/03/19/penalty/ "Penalty: An autopsy of Dead LCD Pixels" at Tom's Hardware Guide]

Hardware Specifications

2006-07-12T08:18:58Z

Hkazemi: /* Available Models */ added TP600

{{Usage|
*Choose a model name to get a list of all currently available information related to this Model.
*Choose a type-and-model number to get the specs of that specific model.
}}
Here you can learn about specific ThinkPads specifications.

Furthermore, you may
*compare the [[ThinkPad series]] (G, R, T, X, Z),
*get an overview of the [[ThinkPad History]] or
*learn about the name [[ThinkPad]].

==IBM/Lenovos hardware specs==
* '''Lenovo ThinkPads'''
** For current Lenovo ThinkPad G, R, T, X and Z series models look for the official specs listed in [ftp://ftp.software.ibm.com/pc/pcinstitute/psref/tabook.pdf tabook.pdf]
** For withdrawn Lenovo ThinkPads, look at [ftp://ftp.software.ibm.com/pc/pcinstitute/psref/ltwbook.pdf ltwbook.pdf]
* '''Withdrawn IBM ThinkPads'''
** For A, G, T and X series models look for the official IBM specs listed in [ftp://ftp.software.ibm.com/pc/pcinstitute/psref/tawbook.pdf tawbook.pdf]
** For R series models look for the official IBM specs listed in [ftp://ftp.software.ibm.com/pc/pcinstitute/psref/trwbook.pdf trwbook.pdf]
** For i series models look for the official IBM specs listed in [ftp://ftp.software.ibm.com/pc/pcinstitute/psref/tiwbook.pdf tiwbook.pdf]
** For 200, 300, 500, 600 and 700 series models look for the official IBM specs listed in [ftp://ftp.software.ibm.com/pc/pcinstitute/psref/twbook.pdf twbook.pdf] 
** Or try searching the IBM announcements letters [http://www.ibm.com/news/usalet/ here].

==Available Models==
{| cellspacing="0" cellpadding="5" border="1"
|- style="text-align:left;"
!Numbered!!A series!!G series!!R series!!S series!!T series!!X series!!Z series!!others
|- style="text-align:left;vertical-align:top;"
|
'''[[:Category:390X | ThinkPad 390X]]'''
*[[2626-L0U]]

'''[[:Category:600 | ThinkPad 600]]'''

'''[[:Category:600E | ThinkPad 600E]]'''

'''[[:Category:600X | ThinkPad 600X]]'''

'''[[:Category:700 | ThinkPad 700]]'''

'''[[:Category:760ED | ThinkPad 760ED]]'''

'''[[:Category:760XD | ThinkPad 760XD]]'''

'''[[:Category:770 | ThinkPad 770]]'''

'''[[:Category:770E | ThinkPad 770E]]'''
*[[9548-510]]
*[[9548-51U]]
*[[9548-52U]]

'''[[:Category:770X | ThinkPad 770X]]'''
*[[9549-7AO]]
'''[[:Category:770Z | ThinkPad 770Z]]'''

||
'''[[:Category:A20m | ThinkPad A20m]]'''

'''[[:Category:A20p | ThinkPad A20p]]'''

'''[[:Category:A21e | ThinkPad A21e]]'''

'''[[:Category:A21m | ThinkPad A21m]]'''

'''[[:Category:A21p | ThinkPad A21p]]'''

'''[[:Category:A22e | ThinkPad A22e]]'''

'''[[:Category:A22m | ThinkPad A22m]]'''

'''[[:Category:A22p | ThinkPad A22p]]'''

'''[[:Category:A30 | ThinkPad A30]]'''

'''[[:Category:A30p | ThinkPad A30p]]'''

'''[[:Category:A31 | ThinkPad A31]]'''

'''[[:Category:A31p | ThinkPad A31p]]'''

||
'''[[:Category:G40 | ThinkPad G40]]'''

'''[[:Category:G41 | ThinkPad G41]]'''

||
'''[[:Category:R30 | ThinkPad R30]]'''

'''[[:Category:R31 | ThinkPad R31]]'''

'''[[:Category:R32 | ThinkPad R32]]'''

'''[[:Category:R40 | ThinkPad R40]]'''
*[[2722-9BM]]
*[[2722-DG1]]

'''[[:Category:R40e | ThinkPad R40e]]'''

'''[[:Category:R50 | ThinkPad R50]]'''
*[[1829-3HU]]

'''[[:Category:R50p | ThinkPad R50p]]'''

'''[[:Category:R50e | ThinkPad R50e]]'''
*[[1834-J8G]]

'''[[:Category:R51 | ThinkPad R51]]'''
*[[1829-K6G]]
*[[1829-L7G]]
*[[1830-DG4]]

'''[[:Category:R52 | ThinkPad R52]]'''
*[[1846-B5G]]
*[[1859-4AU]]

'''[[:Category:R60 | ThinkPad R60]]'''

||
'''[[:Category:S30|ThinkPad S30]]'''

'''[[:Category:S31|ThinkPad S31]]'''
||
'''[[:Category:T20|ThinkPad T20]]'''
*[[2647-44G]]

'''[[:Category:T21|ThinkPad T21]]'''
*[[2647-97G]]

'''[[:Category:T22|ThinkPad T22]]'''

'''[[:Category:T23 | ThinkPad T23]]'''
*[[2647-9RG]]
*[[2647-7G1]]
*[[2647-8QU]]

'''[[:Category:T30 | ThinkPad T30]]'''
*[[2366-52U]]
*[[2366-83U]]
*[[2366-91U]]
*[[2366-FBG]]
*[[2366-GU1]]
*[[2366-JBG]]
*[[2366-R7G]]

'''[[:Category:T40 | ThinkPad T40]]'''

'''[[:Category:T40p | ThinkPad T40p]]'''
*[[2373-G1U]]

'''[[:Category:T41 | ThinkPad T41]]'''

'''[[:Category:T41p | ThinkPad T41p]]'''
*[[2373-315]]
*[[2373-GEG]]
*[[2373-GGG]]
*[[2373-GHG]]

'''[[:Category:T42 | ThinkPad T42]]'''
*[[2373-6ZG]]
*[[2373-9XU]]
*[[2373-CH6]]
*[[2373-F1G]]
*[[2373-F7G]]
*[[2373-FWG]]
*[[2373-M1G]]
*[[2373-VUW]]
*[[2373-WGK]]
*[[2378-FVU]]
*[[2378-RSU]]
*[[2379-DXU]]

'''[[:Category:T42p | ThinkPad T42p]]'''
*[[2373-HTG]]
*[[2373-W6M]]
*[[2373-Y4M]]

'''[[:Category:T43 | Thinkpad T43]]'''
*[[2668-A1U]]
*[[2668-C2U]]
*[[2668-8AG]]

'''[[:Category:T43p | Thinkpad T43p]]'''

'''[[:Category:T60 | ThinkPad T60]]'''

'''[[:Category:T60p | ThinkPad T60p]]'''
||
'''[[:Category:X20 | ThinkPad X20]]'''

'''[[:Category:X21 | ThinkPad X21]]'''
*[[2662-66U]]

'''[[:Category:X22 | ThinkPad X22]]'''
*[[2662-95U]]
*[[2662-9BU]]

'''[[:Category:X23 | ThinkPad X23]]'''

'''[[:Category:X24 | ThinkPad X24]]'''

'''[[:Category:X30 | ThinkPad X30]]'''

'''[[:Category:X31 | ThinkPad X31]]'''

'''[[:Category:X32 | ThinkPad X32]]'''

'''[[:Category:X40 | ThinkPad X40]]'''
*[[2371-AVC]]
'''[[:Category:X41 | ThinkPad X41]]'''

'''[[:Category:X41 Tablet | ThinkPad X41 Tablet]]'''

'''[[:Category:X60 | ThinkPad X60]]'''

'''[[:Category:X60s | ThinkPad X60s]]'''
||
'''[[:Category:Z60t | ThinkPad Z60t]]'''

'''[[:Category:Z60m | ThinkPad Z60m]]'''
||
'''[[:Template:I_Series | I Series]]'''
'''[[:Category:PC110 | PC110]]'''
*[[PC110]]
'''[[:Category:TransNote|TransNote]]'''
*[[2675-61G]]
|}

[[Category:Models]]

Unofficial maximum memory specs

2006-07-04T06:29:19Z

Hkazemi: /* Tested Memory configurations */ TP 600 at 416 mb

Some ThinkPads are known to support more memory than their specs say. This page gathers information about those models, how much memory they can take and what special requirements that memory must fulfill.

Have a look at the [[Memory]] page for the official memory configs and partnumbers

==Tested Memory configurations==
The following table gives an overview of tested memory configurations that exceed the specified limits for that ThinkPad type.

{| border="1" cellspacing="0" cellpadding="2"
! ThinkPad !! max. Specs !! BIOS !! Embedded Controller !! Memory configuration successfully tested
|- style="vertical-align:top;"
| ThinkPad T30 2366-92U || 1 GB || 2.08 || 1.06 ||
* Kingmax 1GB 200-Pin DDR SO-DIMM DDR333 (PC2700) Model # MSAD42D-KI
* Kingmax 1GB 200-Pin DDR SO-DIMM DDR333 (PC2700) Model # MSAD42D-KI
|-
| ThinkPad 240 2609-40U || 320MByte || IRETWWW76 || n/a ||
* Any PC100/256MByte memory in 16 Chip Configuration will do
|-
| ThinkPad 570 2644-3AU || 320MByte || 1.16 IMET65WW 11/11/99 || n/a ||
* Kingston KTM-TP390X/256 256MB MODULE FRU 16P6327 - 16 Chips 8 each side
|-
| ThinkPad 600 ? || 288 mb || ? || ? ||
* 416 mb = 256 mb '''low density''' PC-100 SODIMM + 128 mb PC-66 SODIMM + 32 mb PC-66 onboard (Note: that which SODIMM you put in which slot matters. This was first reported working on the [http://zurich.csail.mit.edu/hypermail/thinkpad/2004-04/0797.html Thinkpad Mailing List], and it worked error-free for me when I tested it.
|-
| ThinkPad A31p 2653-R || 1 GB || 1.09 || 1.05 ||
* Kingston 1GB 200-Pin DDR Model # KTM - TP9828/1G
* Kingston 1GB 200-Pin DDR Model # KTM - TP9828/1G
|-
|}

==External Sources==
*[http://www-307.ibm.com/pc/support/site.wss/document.do?lndocid=MIGR-55644 IBM's official Memory compatibility page]

Category:T23

2006-07-04T06:04:28Z

Hkazemi: ultraport

{| width="100%"
|style="vertical-align:top" |
<div style="margin: 0; margin-right:10px; border: 1px solid #dfdfdf; padding: 0em 1em 1em 1em; background-color:#F8F8FF; align:right;">
=== ThinkPad T23 ===
This page gives an overview of all ThinkPad T23 related topics.
==== Standard Features ====
* [[Intel Mobile Pentium III-M]] 866 MHz, 1.0, 1.13 or 1.2 GHz
* [[S3 SuperSavage IX/C]] with 16 MB
** 13.3" TFT display with 1024x768 resolution
** 14.1" TFT display with 1024x768 resolution
** 14.1" TFT display with 1400x1050 resolution
* 128 or 256 MB [[PC-133]] memory standard, 1 GB (2x512 MB) maximum
* 15, 20, 30, 40, 48 or 60 GB HDD
* [[CS4299]] Audio controller
* [[UltraBay|UltraBay 2000 or UltraBay Plus]] with one of the following:
** CD-ROM drive
** CD-RW drive
** DVD-ROM drive
** DVD-ROM/CD-RW Combo drive
* [[UltraPort]] connector on the top of the display, for use with one of the following:
** default: unused, covered with rubber guard
** [[UltraPort Bluetooth Adapter]]
** [[UltraPort Camera & UltraPort Camera II]]
** [[UltraPort Compact Flash Adapter]]
** [[UltraPort Digital Array Microphone]]
** [[UltraPort Infrared Adapter]]
* [[MiniPCI slot]] with one of the following:
** [[Mini-PCI Modem card]]
** [[IBM High Rate Wireless LAN Mini-PCI Adapter with Modem]]
* [[CDC slot]] with one of the following:
** none (empty)
** 10/100 Mbps [[Ethernet Daughter Card (EDC)]]
* (2) Type II [[CardBus slot|CardBus slots]] or (1) type III
* [[Embedded Security Subsystem|IBM Embedded Security Subsystem]] on select models
* Ports:
** (2) USB v1.1 ports
** PS/2 keyboard/mouse port
** printer port
** serial port
** external monitor port
** S-Video port
** Stereo headphone jack
** Stereo line-in jack
** Microphone jack
* Built-in microphone
</div>
|style="vertical-align:top" |
[[Image:ThinkPadT20.jpg|ThinkPad T23]]
|}

* [ftp://ftp.software.ibm.com/pc/pccbbs/mobiles_pdf/62p9631.pdf T20, T21, T22, T23 - Hardware Maintenance Manual (April 2002)] (2,902,595 Bytes)
[[Category:Models]]