I am using this successfully:
cgminer.exe --scrypt -o stratum+tcp://eac.suprnova.cc:3515 -u name p pw --gridseed-options=baud=115200,freq=800,chips=5 --hotplug 5
do you (or anyone) suggest I change anything?
As bathrobehero said, two different ports to the the same pool. The first one which you are using is probably a vardiff, which means the stratum server will adjust the minimum difficulty it requests from your miner based on an expected timespan. For example if the stratum wants to get a share every 30s, it will over time adjust your difficulty so that your miner with it's given hashrate is able so submit a share around every 30s.
On the other hand if you rent miners from nicehash which start at a minimum of 0.1Gh/s but often go as high as 10Gh/s or even more you need a stratum port with a fixed (very high) difficulty, elsewise if the nicehash miners would start with the same diff as your miner they would try to send hundreds or thousands of low diff shares within the first 30s and overhelm the pool completely., therefor nicehash ports have a fixed high diff like 32768 or 16384.
So if you would point your gridseed toward the nicehash port, you would probably never be able to submit a single share (or it would take a very long time).
That said, your command line above looks fine and like what you should use on that pool.
Never try to use a port labelled with "nicehash" if you have less than 500Mh/s under your mousepointer.
BTW: Your gridseed is an asic miner, so that fits too ;-)
HTH