Are the 2GB a limitation in any way on the claymore miner, as it isn't using a DAG anyways?
Claymore's miner still uses a DAG. It just creates it directly on the GPU, instead of creating it on disk and then uploading it from disk to the GPU. So yes, the 2GB limitation still applies (though it sounds from posts here like 2GB cards are still working for the time being).
Seems like the DAG is around 1,45GB. Thats what my cards use of memory.
Thanks for the input!
How come the miner can start mining almost immediately then?
I'm no expert on Ethereum's PoW algorithm, but I'm guessing because Claymore has written a very fast DAG generator that runs directly on the GPU, and because GPU memory is way, way, way faster than a hard disk. It does take some time--the console messages show that it takes about 5-6 seconds to generate the DAG on each of my GPUs.