Instalando o Steam no ElementaryOS

Question

Estou tentando instalar o Steam no ElementaryOS.

Eu usei o App Center para instalá-lo, mas recebi erros:

desktop:~$ steam
Running Steam on elementary 0.4.1 64-bit
STEAM_RUNTIME is enabled automatically
Installing breakpad exception handler for appid(steam)/version(0)
libGL error: unable to load driver: radeonsi_dri.so
libGL error: driver pointer missing
libGL error: failed to load driver: radeonsi
libGL error: unable to load driver: radeonsi_dri.so
libGL error: driver pointer missing
libGL error: failed to load driver: radeonsi
libGL error: unable to load driver: swrast_dri.so
libGL error: failed to load driver: swrast

Alguém pode me ajudar com isso, por favor? Eu tentei um monte de soluções encontradas em fóruns diferentes, mas infelizmente nenhum resolveu isso.

Obrigado :)

UPDATE # 1: lspci -k

Aqui vai o comando lspci -k retorna:

00:00.0 Host bridge: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor DRAM Controller (rev 09)
    Subsystem: ASRock Incorporation Motherboard
    Kernel driver in use: ivb_uncore
    Kernel modules: ie31200_edac
00:01.0 PCI bridge: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor PCI Express Root Port (rev 09)
    Kernel driver in use: pcieport
    Kernel modules: shpchp
00:02.0 Display controller: Intel Corporation Xeon E3-1200 v2/3rd Gen Core processor Graphics Controller (rev 09)
    Subsystem: ASRock Incorporation Motherboard
    Kernel driver in use: i915
    Kernel modules: i915
00:14.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB xHCI Host Controller (rev 04)
    Subsystem: ASRock Incorporation Motherboard
    Kernel driver in use: xhci_hcd
00:16.0 Communication controller: Intel Corporation 7 Series/C210 Series Chipset Family MEI Controller #1 (rev 04)
    Subsystem: ASRock Incorporation Motherboard
    Kernel driver in use: mei_me
    Kernel modules: mei_me
00:1a.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #2 (rev 04)
    Subsystem: ASRock Incorporation Motherboard
    Kernel driver in use: ehci-pci
00:1b.0 Audio device: Intel Corporation 7 Series/C210 Series Chipset Family High Definition Audio Controller (rev 04)
    Subsystem: ASRock Incorporation 7 Series/C210 Series Chipset Family High Definition Audio Controller
    Kernel driver in use: snd_hda_intel
    Kernel modules: snd_hda_intel
00:1c.0 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 1 (rev c4)
    Kernel driver in use: pcieport
    Kernel modules: shpchp
00:1c.4 PCI bridge: Intel Corporation 82801 PCI Bridge (rev c4)
00:1c.5 PCI bridge: Intel Corporation 7 Series/C210 Series Chipset Family PCI Express Root Port 6 (rev c4)
    Kernel driver in use: pcieport
    Kernel modules: shpchp
00:1d.0 USB controller: Intel Corporation 7 Series/C210 Series Chipset Family USB Enhanced Host Controller #1 (rev 04)
    Subsystem: ASRock Incorporation Motherboard
    Kernel driver in use: ehci-pci
00:1f.0 ISA bridge: Intel Corporation Z77 Express Chipset LPC Controller (rev 04)
    Subsystem: ASRock Incorporation Motherboard
    Kernel driver in use: lpc_ich
    Kernel modules: lpc_ich
00:1f.2 SATA controller: Intel Corporation 7 Series/C210 Series Chipset Family 6-port SATA Controller [AHCI mode] (rev 04)
    Subsystem: ASRock Incorporation Motherboard
    Kernel driver in use: ahci
    Kernel modules: ahci
00:1f.3 SMBus: Intel Corporation 7 Series/C210 Series Chipset Family SMBus Controller (rev 04)
    Subsystem: ASRock Incorporation Motherboard
    Kernel modules: i2c_i801
01:00.0 VGA compatible controller: Advanced Micro Devices, Inc. [AMD/ATI] Cape Verde XT [Radeon HD 7770/8760 / R7 250X]
    Subsystem: Micro-Star International Co., Ltd. [MSI] R7770-PMD1GD5
    Kernel driver in use: radeon
    Kernel modules: radeon, amdgpu
01:00.1 Audio device: Advanced Micro Devices, Inc. [AMD/ATI] Cape Verde/Pitcairn HDMI Audio [Radeon HD 7700/7800 Series]
    Subsystem: Micro-Star International Co., Ltd. [MSI] Cape Verde/Pitcairn HDMI Audio [Radeon HD 7700/7800 Series]
    Kernel driver in use: snd_hda_intel
    Kernel modules: snd_hda_intel
03:00.0 PCI bridge: ASMedia Technology Inc. ASM1083/1085 PCIe to PCI Bridge (rev 01)
04:00.0 FireWire (IEEE 1394): LSI Corporation FW322/323 [TrueFire] 1394a Controller (rev 04)
    Subsystem: Askey Computer Corp. FW322/323 [TrueFire] 1394a Controller
    Kernel driver in use: firewire_ohci
    Kernel modules: firewire_ohci
04:01.0 Non-VGA unclassified device: Qualcomm Atheros AR9285 Wireless Network Adapter (PCI-Express) (rev 01)
    Subsystem: Device 0080:0002
    Kernel modules: ath9k
06:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 06)
    Subsystem: ASRock Incorporation Motherboard (one of many)
    Kernel driver in use: r8169
    Kernel modules: r8169

Espero que possa ajudar um pouco.