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iMac 5K vs Mac Pro, Integrity Checker Verify
Related: 4K and 5K display, CPU cores, data integrity, diglloydTools, iMac, iMac 5K, IntegrityChecker, Mac Pro, Macs, SSD
IntegrityChecker(tm) v1.2.3 64-bit, diglloydTools 2.2.7b
iMac 5K 4.0 GHz, 32GB, 1TB SSD, AMD Radeon R9 M295X 4GB GDDR5 -versus-
2013 Mac Pro 3.3 GHz 8-core, 64GB, 1TB SSD, D700
The two machines tested here are the fastest possible CPUs as of late 2014. The iMac 5K as tested here is well into Mac Pro pricing territory, approaching $5K as configured, though of course it includes the display.
IntegrityChecker verify
diglloydTools IntegrityChecker 'verify' a large set of image files (SHA1 hash). IntegrityChecker is highly optimized for multi-scaling nearly perfectly out to 12 CPU cores, so I/O speed is the gating factor. Here the mix of files limits CPU core usage to about 1.5 CPU cores.
This test is a real-world one in that SSD speed is the gating factor, though the CPU is also involved . The 3.3 GHz 8-core Mac Pro outperforms. which is likely due to its faster SSD.
In theory, the 4 GHZ CPU of the iMac 5K (TurboBoost to 4.4 GHz) should surpass the Mac Pro 3.3 GHz CPU (TurboBoost to 4.0 GHz)—slightly. But it doesn’t pan out when disk I/O is involved, hence the faster SSD in the Mac Pro could be a real advantage for some users.

iMac 5K 4 GHz Radeon M295X vs 2013 Mac Pro 3.3 GHz 8-core D700