PS3 6 SPUs(1 is system reserved) 4-way SIMD PS4 - 18 GCN CUs, each has four 16-ways SIMDs for 72 SIMDs but each is 4 times wider so PS4 has the same number of

PS3 6 SPUs(1 is system reserved) 4-way SIMD PS4 - 18 GCN CUs, each has four 16-ways SIMDs for 72 SIMDs but each is 4 times wider so PS4 has the same number of ways as in 288 4-ways SPUs.