The 78034 was the first VAX microprocessor to have internal caches, a 1 KB combined instruction and data stream cache.[1] The cache is quite different as it is implemented with one-transistor DRAM,[1] whereas the majority of microprocessors use SRAM for their internal caches. This was the first microprocessor to use one-transistor DRAM for cache.[1] DEC chose to use DRAM for the cache to reduce the area of the cache array. The designers concluded that to implement this cache with four-transistor DRAM cells or six-transistor SRAM cells would have taken 2.4 to 3 times more area.[1] The internal cache is located in a narrow strip along the left side of the die. An external 64 KB cache complements the 1 KB internal cache.