matt608, thanks!

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Problem with one card on VTC
HD6970-1GB
system memory 2GB
vertminer don't use --thread-concurrency more then 6016.
because of it HW

Whether it is possible mining VTC on Cgminer?
very sorry for bad english

You MUST use Vertminer, not CGMiner (unless it is the patched version - but it seems easier just to use the actual Vertminer program). May account for your hardware errors.
Also, for higher thread-concurrency, you're going to need more physical RAM.