GRIN cryptocurrency mining initially had high demands on video memory (8Gb for GRIN29 and 10GB for GRIN31), but with improved optimization of miners, now mining GRIN is available starting from 4Gb for GRIN29 and 8GB for GRIN31. The first miner who proposed mining GRIN29 on 4GB video cards was KBMiner built into the MinerBabe OS. The popular Gminer only in the current version 1.38 received support for mining on the Cuckaroo29 algorithm using AMD and NVIDIA video cards with 4GB of video memory on board, though only for Linux and Windows 7. Gminer is distributed with closed source code and a 2% commission. You can download the latest version on Bitcointalk..