A computer allows non-cacheable loads or stores in a hardware transactional memory environment. Transactional loads or stores, by a processor, are monitored in a cache for TX conflicts. The processor accepts a request to execute a transactional execution (TX) transaction. Based on processor execution of a cacheable load or store instruction for loading or storing first memory data of the transaction, the computer can perform a cache miss operation on the cache. Based on processor execution of a non-cacheable load instruction for loading second memory data of the transaction, the computer can not-perform the cache miss operation on the cache based on a cache line associated with the second memory data being not-cached, and load an address of the second memory data into a non-cache-monitor. The TX transaction can be aborted based on the non-cache monitor detecting a memory conflict from another processor.