I need help with an engine error

I downloaded this map http://www.garrysmod.org/downloads/?a=view&id=5959 and whenever I load it up it says “failed to lock vertex buffer in CMeshDX8::LockVertexBuffer” I have tried redownloading and verifying im not really good at fixing this kind of stuff I need some help. Thanks.

Maybe you have DirectX 8 gpu and that map may have problems with DX 8? So I guess there is no way to fix it…