Lenovo ThinkPad T420 User Manual

4 Fanlouvers(rear)
Theinternalfanandlouversenableairtocirculateinthecomputerandcoolthecentralprocessor.
Note:Toavoidimpedingairow,donotplaceanyobstacleinfrontofthefan.
Statusindicators
Thestatusindicatorsshowthecurrentstatusofyourcomputer.
System-statusindicators
1 DeviceAccess
Aharddiskdriveoranoptionaldrive,suchasadriveintheUltrabay,isbeingusedtoreadorwritedata.
Whenthisindicatorisblinking,donotputthecomputerintosleep(standby)mode,removethe
devicefromthebay,orturnoffthecomputer.
2 PowerOn
Thepowerswitchstayslitwheneverthecomputerison,blinkswhenthecomputerisinsleep(standby)
mode,andisoffwhenthecomputerisoff.
3 CapsLock
CapsLockmodeisenabled.Youcanenterallalphabeticcharacters(A-Z)inuppercasewithoutpressing
theShiftkey.
4 Numericlock
Bydefault,whenthenumericlockison,thenumericlockindicatorisdisplayedonthescreen.Tochangethe
settingsofthenumericlockindicator,see“Changingdisplaysettings”onpage69.
Note:Anothermodeavailableforyourcomputer,thoughthereisnoindicatorforit,isScrollLockmode.
Whenthismodeisenabled,thearrowkeyscanbeusedasfunctionkeysforscreen-scrolling,butnotfor
Chapter1.ProductOverview11

Lenovo ThinkPad T420 Specifications

General

Processor cache	3 MB
Processor front side bus	1333 MHz
Number of processors supported	1
Display diagonal	14 \
Display resolution	1366 x 768 pixels
AC adapter power	65 W
Indication light	Yes
Infrared data port	No
Number of speakers	2
Maximum internal memory	8 GB
Speaker power	1 W
Battery voltage	10.8 V
HDD speed	7200 RPM
HDD capacity	320 GB
HDD interface	SATA

Weight and Dimensions

Depth	337 mm
Height	21.2 mm
Height (imperial)	0.83 \