Проблема с процессором AMD APU-A4-5000

Я недавно установил Ubuntu 14.04 на свой ноутбук Toshiba Satellite C50D-A 40010 (PSCGYG-00J00J). Скорость моего процессора AMD A4 составляет 1,5 ГГц, но Ubuntu показывает 800 МГц.

dharmesh@home:~$ cat /proc/cpuinfo 
processor   : 0
vendor_id   : AuthenticAMD
cpu family  : 22
model       : 0
model name  : AMD A4-5000 APU with Radeon(TM) HD Graphics
stepping    : 1
microcode   : 0x700010b
cpu MHz     : 800.000
cache size  : 2048 KB
physical id : 0
siblings    : 4
core id     : 0
cpu cores   : 4
apicid      : 0
initial apicid  : 0
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc extd_apicid aperfmperf eagerfpu pni pclmulqdq monitor ssse3 cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt topoext perfctr_nb perfctr_l2 arat xsaveopt hw_pstate proc_feedback npt lbrv svm_lock nrip_save tsc_scale flushbyasid decodeassists pausefilter pfthreshold bmi1
bogomips    : 2994.37
TLB size    : 1024 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 40 bits physical, 48 bits virtual
power management: ts ttp tm 100mhzsteps hwpstate [11]

processor   : 1
vendor_id   : AuthenticAMD
cpu family  : 22
model       : 0
model name  : AMD A4-5000 APU with Radeon(TM) HD Graphics    
stepping    : 1
microcode   : 0x700010b
cpu MHz     : 800.000
cache size  : 2048 KB
physical id : 0
siblings    : 4
core id     : 1
cpu cores   : 4
apicid      : 1
initial apicid  : 1
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc extd_apicid aperfmperf eagerfpu pni pclmulqdq monitor ssse3 cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt topoext perfctr_nb perfctr_l2 arat xsaveopt hw_pstate proc_feedback npt lbrv svm_lock nrip_save tsc_scale flushbyasid decodeassists pausefilter pfthreshold bmi1
bogomips    : 2994.37
TLB size    : 1024 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 40 bits physical, 48 bits virtual
power management: ts ttp tm 100mhzsteps hwpstate [11]

processor   : 2
vendor_id   : AuthenticAMD
cpu family  : 22
model       : 0
model name  : AMD A4-5000 APU with Radeon(TM) HD Graphics    
stepping    : 1
microcode   : 0x700010b
cpu MHz     : 1300.000
cache size  : 2048 KB
physical id : 0
siblings    : 4
core id     : 2
cpu cores   : 4
apicid      : 2
initial apicid  : 2
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc extd_apicid aperfmperf eagerfpu pni pclmulqdq monitor ssse3 cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt topoext perfctr_nb perfctr_l2 arat xsaveopt hw_pstate proc_feedback npt lbrv svm_lock nrip_save tsc_scale flushbyasid decodeassists pausefilter pfthreshold bmi1
bogomips    : 2994.37
TLB size    : 1024 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 40 bits physical, 48 bits virtual
power management: ts ttp tm 100mhzsteps hwpstate [11]

processor   : 3
vendor_id   : AuthenticAMD
cpu family  : 22
model       : 0
model name  : AMD A4-5000 APU with Radeon(TM) HD Graphics    
stepping    : 1
microcode   : 0x700010b
cpu MHz     : 800.000
cache size  : 2048 KB
physical id : 0
siblings    : 4
core id     : 3
cpu cores   : 4
apicid      : 3
initial apicid  : 3
fpu     : yes
fpu_exception   : yes
cpuid level : 13
wp      : yes
flags       : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush mmx fxsr sse sse2 ht syscall nx mmxext fxsr_opt pdpe1gb rdtscp lm constant_tsc rep_good nopl nonstop_tsc extd_apicid aperfmperf eagerfpu pni pclmulqdq monitor ssse3 cx16 sse4_1 sse4_2 movbe popcnt aes xsave avx f16c lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt topoext perfctr_nb perfctr_l2 arat xsaveopt hw_pstate proc_feedback npt lbrv svm_lock nrip_save tsc_scale flushbyasid decodeassists pausefilter pfthreshold bmi1
bogomips    : 2994.37
TLB size    : 1024 4K pages
clflush size    : 64
cache_alignment : 64
address sizes   : 40 bits physical, 48 bits virtual
power management: ts ttp tm 100mhzsteps hwpstate [11]