DCS 2.5.6 is an older version of the sim that is far more performance-friendly, with lower hardware requirements.

This package provides the necessary files to easily (and separately) download and install DCS 2.5.6 (its final Stable release 2.5.6.61527.3, March 5th 2021) from ED's official servers. Just follow the instructions provided with the download package.

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Are you frustrated that your PC is not enough for newest versions of DCS, that the performance is unacceptable?
Want to run VR, and it runs poor with a capable machine, even at low settings?
Tired of the inconsistent framerate, frametime or the constant micro-stutters, or the slow loading at the start and on missions loading?  
If you are, then reverting to this older DCS version might be the solution for you to better enjoy the sim.

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For DCS 2.5.6, I also suggest these two following mods:

-  CGTC, which vastly improves the looks of the Caucasus map in DCS 2.5.6:         https://www.digitalcombatsimulator.com/en/files/3321589/
-  SIMPLEX 2.56, a shaders pack that further improves performance (if needed):   https://www.digitalcombatsimulator.com/en/files/3317942/

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- NEW MODULES / MAPS RELEASED AFTER APRIL 2021 DO NOT WORK WITH THIS VERSION
- THIS VERSION WORKS IN MULTIPLAYER BUT IT IS NOT COMPATIBLE WITH ANY OTHER VERSIONS
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