Why does the driver crash when creating/destroying many VertexBuffers

When I create several VertexBuffers, destroy some of them, then recreate them, I get the following error:

The driver has encountered an unexpected error.

No line number or other debug information is provided. What could be causing this? I need to constantly re-create 开发者_如何学JAVAVertexBuffers, because the number of vertices changes, which is why I can't use a DynamicVertexBuffer and use SetData continuously.

OK. Apparently; I can only Dispose() of five VertexBuffers at a time, so on each call to Draw, I only dispose a maximum of five VertexBuffers, and it works perfectly. This works, but it would still be nice to know WHY it works, and what caused it to crash to begin with.