Same problem.

:~$ uname -a
Linux vagrale-desktop 4.8.0-58-generic #63~16.04.1-Ubuntu SMP Mon Jun 26 17:59:49 UTC 2017 i686 athlon i686 GNU/Linux


:~$ sudo dmidecode -t processor | grep Speed
	Max Speed: 2700 MHz
	Current Speed: 3052 MHz


:~$ dmesg | grep MHz
[    0.000000] tsc: Detected 3033.770 MHz processor
[    1.955784] tsc: Refined TSC clocksource calibration: 3033.664 MHz


:~$ lscpu | grep MHz
CPU MHz:               1500.000
CPU max MHz:           2700,0000
CPU min MHz:           800,0000


:~$ cpupower -c all frequency-info
analyzing CPU 0:
  driver: acpi-cpufreq
  CPUs which run at the same hardware frequency: 0
  CPUs which need to have their frequency coordinated by software: 0
  maximum transition latency: 4.0 us
  hardware limits: 800 MHz - 2.70 GHz
  available frequency steps:  2.70 GHz, 2.10 GHz, 1.50 GHz, 800 MHz
  available cpufreq governors: conservative ondemand userspace powersave performance
  current policy: frequency should be within 800 MHz and 2.70 GHz.
                  The governor "ondemand" may decide which speed to use
                  within this range.
  current CPU frequency: Unable to call hardware
  current CPU frequency: 2.10 GHz (asserted by call to kernel)
  boost state support:
    Supported: no
    Active: no

analyzing CPU 1:
  driver: acpi-cpufreq
  CPUs which run at the same hardware frequency: 1
  CPUs which need to have their frequency coordinated by software: 1
  maximum transition latency: 4.0 us
  hardware limits: 800 MHz - 2.70 GHz
  available frequency steps:  2.70 GHz, 2.10 GHz, 1.50 GHz, 800 MHz
  available cpufreq governors: conservative ondemand userspace powersave performance
  current policy: frequency should be within 800 MHz and 2.70 GHz.
                  The governor "ondemand" may decide which speed to use
                  within this range.
  current CPU frequency: Unable to call hardware
  current CPU frequency: 2.70 GHz (asserted by call to kernel)
  boost state support:
    Supported: no
    Active: no


:~$ cat /proc/cpuinfo
processor	: 0
vendor_id	: AuthenticAMD
cpu family	: 16
model		: 6
model name	: AMD Athlon(tm) X2 215 Processor
stepping	: 2
microcode	: 0x10000c7
cpu MHz		: 1500.000
cache size	: 512 KB
physical id	: 0
siblings	: 2
core id		: 0
cpu cores	: 2
apicid		: 0
initial apicid	: 0
fdiv_bug	: no
f00f_bug	: no
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 5
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 3dnowext 3dnow constant_tsc rep_good nonstop_tsc extd_apicid eagerfpu pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt hw_pstate vmmcall npt lbrv svm_lock nrip_save
bugs		: tlb_mmatch apic_c1e fxsave_leak sysret_ss_attrs
bogomips	: 6067.54
clflush size	: 64
cache_alignment	: 64
address sizes	: 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate

processor	: 1
vendor_id	: AuthenticAMD
cpu family	: 16
model		: 6
model name	: AMD Athlon(tm) X2 215 Processor
stepping	: 2
microcode	: 0x10000c7
cpu MHz		: 800.000
cache size	: 512 KB
physical id	: 0
siblings	: 2
core id		: 1
cpu cores	: 2
apicid		: 1
initial apicid	: 1
fdiv_bug	: no
f00f_bug	: no
coma_bug	: no
fpu		: yes
fpu_exception	: yes
cpuid level	: 5
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 3dnowext 3dnow constant_tsc rep_good nonstop_tsc extd_apicid eagerfpu pni monitor cx16 popcnt lahf_lm cmp_legacy svm extapic cr8_legacy abm sse4a misalignsse 3dnowprefetch osvw ibs skinit wdt hw_pstate vmmcall npt lbrv svm_lock nrip_save
bugs		: tlb_mmatch apic_c1e fxsave_leak sysret_ss_attrs
bogomips	: 6067.54
clflush size	: 64
cache_alignment	: 64
address sizes	: 48 bits physical, 48 bits virtual
power management: ts ttp tm stc 100mhzsteps hwpstate