after "pacman -S nouveau-dri xf86-video-nouveau #lib32-nouveau-dri" card is working fine with 3d (no problem playing openarena with quite some details). 2d also good (cinnamon effects are working)
$ lspci -vv
02:00.0 VGA compatible controller: NVIDIA Corporation GK104 [GeForce GTX 760] (rev a1) (prog-if 00 [VGA controller])
Subsystem: CardExpert Technology Device 1187
Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR+ FastB2B- DisINTx-
Status: Cap+ 66MHz- UDF- FastB2B- ParErr- DEVSEL=fast >TAbort- <TAbort- <MAbort- >SERR- <PERR- INTx-
Latency: 0, Cache Line Size: 64 bytes
Interrupt: pin A routed to IRQ 24
Region 0: Memory at fa000000 (32-bit, non-prefetchable) [size=16M]
Region 1: Memory at d8000000 (64-bit, prefetchable) [size=128M]
Region 3: Memory at d6000000 (64-bit, prefetchable) [size=32M]
Region 5: I/O ports at ac00 [size=128]
Expansion ROM at fba00000 [disabled] [size=512K]
Capabilities: <access denied>
Kernel driver in use: nouveau
Kernel modules: nouveau
modèle: NVIDIA Corporation GK104 [GeForce GTX 760] (rev a1)(ID du modèle: 1208)
