It's not too crazy, the GPU is usually only ~1GHz, whereas modern CPUs are ~2-3GHz. So the double clock speed puts it right in the range as a modern CPU, just with many more ALUs.
Computer memory (DDR3 for example) also runs at twice the clock rate (Double Data Rate), and in some modern CPUs it isn't unheard of to have a few different clocks within the CPU itself (generally for the I/O buses).
Pretty crazy that ALUs run twice as fast here.
It's not too crazy, the GPU is usually only ~1GHz, whereas modern CPUs are ~2-3GHz. So the double clock speed puts it right in the range as a modern CPU, just with many more ALUs.
Computer memory (DDR3 for example) also runs at twice the clock rate (Double Data Rate), and in some modern CPUs it isn't unheard of to have a few different clocks within the CPU itself (generally for the I/O buses).