It would be prohibitively expensive. Several megabytes of cache already take up about half of the CPU die size. http://techreport.com/review/21987/intel-core-i

It would be prohibitively expensive. Several megabytes of cache already take up about half of the CPU die size. http://techreport.com/review/21987/intel-core-i7-3960x-processor http://techreport.com/review/21987/intel-core-i7-3960x-proce... Think about how much larger a CPU would have to be to include an entire gigabyte of cache, much less multiple gigabytes.