As part of a presentation I did at a local OWASP chapter, here are some numbers based on just using CPython's Hashlib processing of 14,000,000 someodd passwords:

Intel Xeon E5-1620 3.6 GHz: SHA: 8.16 seconds, SHA256: 11.01 seconds, MD5: 8.7 seconds

AMD FX-8320 3.5 GHz: SHA: 10.63 seconds, SHA256: 13.49 seconds, MD5: 10.06 second

Intel Celeron N2840 2.2 GHz: SHA: 32.4 seconds, SHA256: 39.75 seconds, MD5: 28.95 seconds

Intel Pentium M 1.7 GHz: SHA: 37.98 seconds, SHA256: 48.12 seconds, MD5: 34.49 seconds

SHA512 isn't going to make it much better.