https://bitcointalk.org/index.php?topic=4978579.0 has a miner that is not limited by the DAG size. It uses paging to the system memory from the GPU RAM to get around the issues. I've run it without issues. Performance is slightly degraded due to the hit to get to system memory but it is only 5% slower than what it used to be.
1. This mining tool is a scam/virus.
2. Now the DAG file for Ethereum is 2.66 GB you have another 6 months for mining with those cards if you install Windows 7 or ethos or any other linux based mining software. After that period you can move to Ubiq or other coin