dump_psb: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/dump_psb - from package: cpufrequtils

You may install the required package with command yum install {package}

Error in other languages:
dump_psb: bevel nie gevind nie
dump_psb: comandă negăsită
dump_psb: comando não encontrado
dump_psb: commande introuvable
dump_psb: command not found
dump_psb: käsku ei ole
dump_psb: không tìm thấy lệnh
dump_psb: komanda nerasta
dump_psb: Kommando nicht gefunden.
dump_psb: kommandot finns inte
dump_psb: komut yok
dump_psb: nie znaleziono polecenia
dump_psb: níor aimsíodh an t-ordú
dump_psb: no se encontró la orden
dump_psb: no s'ha trobat l'ordre
dump_psb: opdracht niet gevonden
dump_psb: parancs nem található
dump_psb: perintah tidak ditemukan
dump_psb: príkaz nenájdený
dump_psb: příkaz nenalezen
dump_psb: команда не найдена
dump_psb: командата не е открита
dump_psb: 命令找不到
dump_psb: コマンドが見つかりません