Maximum allowed frequency is 1.51GHz on 2.0.8 TinkerOS

[Z80]

Just tried mt08 codes with a fresh 2.0.8  image, still only getting 1.6 (it was 1.5  before i tried mt08 code)
I am on the version 1 tinkerboard (i.e. has V1 stamped on pcb, think there is a v2 version)
I have 5 volt direct to gpio with a fan. can someone who says its working try doing lscpu on their machine and show the results?

lscpu

Model:                 1
Model name:            ARMv7 Processor rev 1 (v7l)
CPU max MHz:           1608.0000
CPU min MHz:           126.0000
BogoMIPS:              48.00
Flags:                 half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm
linaro@tinkerboard:~$ lscpu
Architecture:          armv7l
Byte Order:            Little Endian
CPU(s):                4
On-line CPU(s) list:   0-3
Thread(s) per core:    1
Core(s) per socket:    4
Socket(s):             1
Model:                 1
Model name:            ARMv7 Processor rev 1 (v7l)
CPU max MHz:           1608.0000
CPU min MHz:           126.0000
BogoMIPS:              48.00
Flags:                 half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm
linaro@tinkerboard:~$ ^C
linaro@tinkerboard:~$

Hi Z80,

Can you make sure md5sum of /boot/rk3288-miniarm.dtb ?
My cmd replaces only this file.

Code:

linaro@tinkerboard:~$ md5sum /boot/rk3288-miniarm.dtb
ce70fbd5cf42cc3e4d9728612837887e  /boot/rk3288-miniarm.dtb
linaro@tinkerboard:~$ lscpu
Architecture:          armv7l
Byte Order:            Little Endian
CPU(s):                4
On-line CPU(s) list:   0-3
Thread(s) per core:    1
Core(s) per socket:    4
Socket(s):             1
Model:                 1
Model name:            ARMv7 Processor rev 1 (v7l)
CPU max MHz:           1800.0000
CPU min MHz:           126.0000
BogoMIPS:              48.00
Flags:                 half thumb fastmult vfp edsp thumbee neon vfpv3 tls vfpv4 idiva idivt vfpd32 lpae evtstrm
linaro@tinkerboard:~$

yes dtb file had been replaced, i tried lscpu before your mode and got 1.5  after i get 1.6. 
i might try another psu to my tinjer and see if that makes a differnece. i also unplugged everything from the usb sockets to reduce power bit still get 1.6.
my tinker board is a v1.2 on pcb, i think there is a v2 pcb