NVENC : fail to compress H264 with for multiple video streams

I have two Quadro K620 NVidia video cards. I want to compress 4 H.264 streams using NVENC SDK, 2 streams per card. video is 640x 480 30 fps.

2 streams working well without any problem but It’s failed when I try to encod 3 Streams.

The function nvEncOpenEncodeSessionEx return NV_ENC_ERR_OUT_OF_MEMORY error in 3th stream.

Any idea?


The current SDK package allows up to two
simultaneous encode sessions per system for low-end
Quadro and GeForce cards. If the system contains any
low-end hardware (even in conjunction with other
high-end hardware), only two encoding sessions will
be permitted.

– from NVENC_DA-06209-001_v06.pdf in docs of NVENC SDK

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