t400有幾多個版本??

我see到有部t400(p8700)學生價....但hardware/software同街外的t400唔同ge??-.-但又一樣叫t400wo...係咪一樣叫t400有好多個版本ga??
唔同ge地方有:
街外的t400有vista business,320gb(5400rpm),2*ddr3-1066mhz,14.1WXGA+LEDblacklight
學生價t400....vista home basic, 320gb(7200rpm),1*ddr3-1066mhz,14.1WXGA(LEDblacklight無左??)
學生價t400link: http://www.hkedoffer.com/ive2009/t4008.htm
想問下學生價t400同街外的t400用落分別大唔大??(用wifi來上下網,一般文書,autoCAD)
如果+$438有Microsoft Optical Mouse+Screen Protector+Kaspersky AV 2010+DDR3 2GB RAM低唔低ar??