Need to change refresh rate

[Malvazar]

Okay so I just updated to Mint 18.3 from 17.3. Before I was able to install the Radeon drivers and had access to the Radeon settings panel. Now it seems that’s not going to be an option, which is a problem for me. I have a dual monitor setup:
1. 1920x1200 Monitor
2. 4096x2160 TV

The monitor works fine, its the TV that’s the problem. Its supposed to be running at 30Hrz when in 4k, but I know by default that Linux sets it to 24Hrz. This wasn't a problem on Mint 17.3, I'd just set it to 30Hrz in the Radeon panel. I don't have to option now though, so I need to know what I can do to fix this problem.
All of my system info is listed below.

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System:    Host: malvazar-linux Kernel: 4.13.0-39-generic x86_64 (64 bit gcc: 5.4.0)
           Desktop: Cinnamon 3.6.6 (Gtk 3.18.9-1ubuntu3.3)
           Distro: Linux Mint 18.3 Sylvia
           
Machine:   Mobo: MSI model: 970 GAMING (MS-7693) v: 4.0
           Bios: American Megatrends v: V22.2 date: 12/16/2014
           
CPU:       Octa core AMD FX-8350 Eight-Core (-MCP-) cache: 16384 KB
           flags: (lm nx sse sse2 sse3 sse4_1 sse4_2 sse4a ssse3 svm) bmips: 63998
           clock speeds: max: 4096 MHz 1: 4096 MHz 2: 4093 MHz 3: 4095 MHz
           4: 4095 MHz 5: 4094 MHz 6: 4093 MHz 7: 4095 MHz 8: 4095 MHz
           
Graphics:  Card-1: Advanced Micro Devices [AMD/ATI] Tonga PRO [Radeon R9 285/380]
           bus-ID: 01:00.0
           Card-2: Advanced Micro Devices [AMD/ATI] Tonga PRO [Radeon R9 285/380]
           bus-ID: 02:00.0
           Display Server: X.Org 1.18.4 drivers: ati,amdgpu (unloaded: fbdev,vesa,radeon)
           Resolution: 4096x2160@24.00hz, 1920x1200@59.95hz
           GLX Renderer: AMD Radeon R9 380 Series (AMD TONGA / DRM 3.18.0 / 4.13.0-39-generic, LLVM 5.0.0)
           GLX Version: 3.0 Mesa 17.2.8 Direct Rendering: Yes
           
Audio:     Card-1 2x Advanced Micro Devices [AMD/ATI] Tonga HDMI Audio [Radeon R9 285/380]
           driver: snd_hda_intelsnd_hda_intel bus-ID: 02:00.1
           Card-2 Advanced Micro Devices [AMD/ATI] SBx00 Azalia (Intel HDA)
           driver: snd_hda_intel bus-ID: 00:14.2
           Sound: Advanced Linux Sound Architecture v: k4.13.0-39-generic
           
Network:   Card: Qualcomm Atheros Killer E220x Gigabit Ethernet Controller
           driver: alx port: c000 bus-ID: 06:00.0
           IF: enp6s0 state: up speed: 100 Mbps duplex: full mac: <filter>
           
Drives:    HDD Total Size: 1750.4GB (2.6% used)
           ID-1: /dev/sda model: Hitachi_HTS72755 size: 500.1GB
           ID-2: /dev/sdb model: Samsung_SSD_850 size: 250.1GB
           ID-3: /dev/sdd model: SAMSUNG_HD103SI size: 1000.2GB
           
Partition: ID-1: / size: 443G used: 27G (7%) fs: ext4 dev: /dev/dm-1
           ID-2: /boot size: 472M used: 133M (30%) fs: ext2 dev: /dev/sda1
           ID-3: swap-1 size: 17.12GB used: 0.00GB (0%) fs: swap dev: /dev/dm-3
           
RAID:      No RAID devices: /proc/mdstat, md_mod kernel module present

Sensors:   System Temperatures: cpu: 27.4C mobo: N/A gpu: 48.0,40.0
           Fan Speeds (in rpm): cpu: N/A
           
Info:      Processes: 301 Uptime: 36 min Memory: 2481.5/15989.3MB
           Init: systemd runlevel: 5 Gcc sys: 5.4.0
           Client: Shell (bash 4.3.481) inxi: 2.2.35