▁Some ▁of ▁these ▁are ▁available ▁through ▁the ▁B OIN C ▁client , ▁others ▁through ▁the ▁PR P Net ▁client . ▁Some ▁of ▁the ▁work ▁is ▁manual , ▁i . e . ▁it ▁requires ▁manually ▁starting ▁work ▁units ▁and ▁upload ing ▁results . ▁D ifferent ▁sub projects ▁may ▁run ▁on ▁different ▁operating ▁systems , ▁and ▁may ▁have ▁execut ables ▁for ▁CPU s , ▁GPU s , ▁or ▁both ; ▁while ▁running ▁the ▁Lucas – Le h mer – R ies el ▁test , ▁CPU s ▁with ▁Advanced ▁Vector ▁Ext ensions ▁and ▁F used ▁Mult ip ly - Add ▁instruction ▁sets ▁will ▁yield ▁the ▁fast est ▁results ▁for ▁non - G PU ▁acceler ated ▁work loads . ▁ ▁Prime Grid ▁awards ▁bad ges ▁to ▁users ▁in ▁recognition ▁of ▁ach ieving ▁certain ▁defined ▁levels ▁of ▁credit ▁for ▁work ▁done . ▁The ▁bad ges ▁are ▁of ▁no ▁intr insic ▁value ▁but ▁are ▁val ued ▁by ▁many ▁as ▁a ▁sign ▁of ▁achiev ement . ▁The ▁issu ing ▁of ▁bad ges ▁should ▁also ▁benefit ▁Prime Grid ▁by ▁evening ▁out ▁the ▁participation ▁in ▁the ▁less ▁popular ▁sub ▁projects . ▁The ▁easiest ▁of ▁the ▁bad ges ▁can ▁often ▁be ▁obtained ▁in ▁less ▁than ▁a ▁day ▁by ▁a ▁single ▁computer , ▁whereas ▁the ▁most ▁challeng ing ▁bad ges ▁will ▁require ▁far ▁more ▁time ▁and ▁computing ▁power . ▁ ▁History ▁Prime Grid ▁started ▁in ▁June ▁ 2 0 0 5 ▁under ▁the ▁name ▁Message @ home ▁and ▁tried ▁to ▁de ci pher ▁text ▁fragments ▁hash ed ▁with ▁MD 5 . ▁Message @ home