CPU speed vs efficiency

I have been tasked with finding a lower power consuming solution while preserving performance.

The chart below is sorted by Total CPU performance but there are also other factors such as can your application use 4 CPU's or will it just be limited to one or two while the rest go unused.

We are currently using an i5-650 that is 73 watts for 2 core at 3.2 GHz.  I quick look shows the i3-3225  at 55 watts for what is a slight performance gain of 2 cores at 3.3 Ghz.


I found it interesting that there was such a strong relationship between lower CPU speeds and more efficient operation. I can't help but feel this is more then physics at work but more organizational mandates and a side effect of the way their requirements are put together.






This is across all Intel CPU's after 2006 or so up to the current ones shipped. 
Speed is (GHz * Cores) / 21 , the fasted being the i7-3970X 6 cores at 3.5 GHz. 

	CPU Model	Clock GHz	# of Cores	TPD Watts	Speed (Clock*Cores)	Efficiency (Ghz / Watt)
	i7-3970X	3.5	6	150	21	0.14
	i7-990X	3.47	6	130	20.82	0.16
	i7-980	3.33	6	130	19.98	0.154
	i7-980X	3.33	6	130	19.98	0.154
	i7-3960X	3.3	6	130	19.8	0.152
	i7-970	3.2	6	130	19.2	0.148
	i7-3930K	3.2	6	130	19.2	0.148
	i7-3820	3.6	4	130	14.4	0.111
	i7-2700K	3.5	4	95	14	0.147
	i7-3770K	3.5	4	77	14	0.182
	i5-2550K	3.4	4	95	13.6	0.143
	i7-2600	3.4	4	95	13.6	0.143
	i7-2600K	3.4	4	95	13.6	0.143
	i5-3570	3.4	4	77	13.6	0.177
	i5-3570K	3.4	4	77	13.6	0.177
	i7-3770	3.4	4	77	13.6	0.177
	i7-975	3.33	4	130	13.32	0.102
	i5-2500	3.3	4	95	13.2	0.139
	i5-2500K	3.3	4	95	13.2	0.139
	i5-3550	3.3	4	77	13.2	0.171
	i7-960	3.2	4	130	12.8	0.098
	i7-965	3.2	4	130	12.8	0.098
	i5-2450P	3.2	4	95	12.8	0.135
	i5-3470	3.2	4	77	12.8	0.166
	i5-2380P	3.1	4	95	12.4	0.131
	i5-2400	3.1	4	95	12.4	0.131
	i5-3450	3.1	4	77	12.4	0.161
	i5-3350P	3.1	4	69	12.4	0.18
	i5-3570S	3.1	4	65	12.4	0.191
	i7-3770S	3.1	4	65	12.4	0.191
	i7-950	3.07	4	130	12.28	0.094
	i7-880	3.07	4	95	12.28	0.129
	i5-2320	3	4	95	12	0.126
	i5-3330	3	4	77	12	0.156
	i5-3550S	3	4	65	12	0.185
	i7-3940XM	3	4	55	12	0.218
	i7-940	2.93	4	130	11.72	0.09
	i7-870	2.93	4	95	11.72	0.123
	i7-875K	2.93	4	95	11.72	0.123
	i5-2310	2.9	4	95	11.6	0.122
	i5-3470S	2.9	4	65	11.6	0.178
	i5-3475S	2.9	4	65	11.6	0.178
	i7-3920XM	2.9	4	55	11.6	0.211
	i7-930	2.8	4	130	11.2	0.086
	i5-760	2.8	4	95	11.2	0.118
	i5-2300	2.8	4	95	11.2	0.118
	i7-860	2.8	4	95	11.2	0.118
	i5-3450S	2.8	4	65	11.2	0.172
	i7-2600S	2.8	4	65	11.2	0.172
	i7-3840QM	2.8	4	45	11.2	0.249
	i5-2500S	2.7	4	65	10.8	0.166
	i5-3330S	2.7	4	65	10.8	0.166
	i5-3335S	2.7	4	65	10.8	0.166
	i7-2960XM	2.7	4	55	10.8	0.196
	i7-3740QM	2.7	4	45	10.8	0.24
	i7-3820QM	2.7	4	45	10.8	0.24
	i7-920	2.67	4	130	10.68	0.082
	i5-750	2.67	4	95	10.68	0.112
	i7-870S	2.67	4	82	10.68	0.13
	i7-3720QM	2.6	4	45	10.4	0.231
	i7-860S	2.53	4	82	10.12	0.123
	i5-2400S	2.5	4	65	10	0.154
	i5-2405S	2.5	4	65	10	0.154
	i7-2920XM	2.5	4	55	10	0.182
	i7-3770T	2.5	4	45	10	0.222
	i7-2860QM	2.5	4	45	10	0.222
	i5-750s	2.4	4	82	9.6	0.117
	i7-2760QM	2.4	4	45	9.6	0.213
	i7-3630QM	2.4	4	45	9.6	0.213
	i7-3635QM	2.4	4	45	9.6	0.213
	i5-2500T	2.3	4	45	9.2	0.204
	i5-3570T	2.3	4	45	9.2	0.204
	i7-2820QM	2.3	4	45	9.2	0.204
	i7-3610QM	2.3	4	45	9.2	0.204
	i7-3615QM	2.3	4	45	9.2	0.204
	i7-3610QE	2.3	4	45	9.2	0.204
	i7-3615QE	2.3	4	45	9.2	0.204
	i7-2670QM	2.2	4	45	8.8	0.196
	i7-2675QM	2.2	4	45	8.8	0.196
	i7-2720QM	2.2	4	45	8.8	0.196
	i7-3632QM	2.2	4	35	8.8	0.251
	i7-940XM	2.13	4	55	8.52	0.155
	i7-2710QE	2.1	4	45	8.4	0.187
	i7-2715QE	2.1	4	45	8.4	0.187
	i7-3612QM	2.1	4	35	8.4	0.24
	i7-3612QE	2.1	4	35	8.4	0.24
	i7-920XM	2	4	55	8	0.145
	i7-2630QM	2	4	45	8	0.178
	i7-2635QM	2	4	45	8	0.178
	i7-840QM	1.87	4	45	7.48	0.166
	i5-680	3.6	2	73	7.2	0.099
	i5-670	3.47	2	73	6.94	0.095
	i7-740QM	1.73	4	45	6.92	0.154
	i7-820QM	1.73	4	45	6.92	0.154
	i3-2130	3.4	2	65	6.8	0.105
	i3-3240	3.4	2	55	6.8	0.124
	i5-661	3.33	2	87	6.66	0.077
	i5-660	3.33	2	73	6.66	0.091
	i3-560	3.33	2	73	6.66	0.091
	i3-2120	3.3	2	65	6.6	0.102
	i3-2125	3.3	2	65	6.6	0.102
	i3-3220	3.3	2	55	6.6	0.12
	i3-3225	3.3	2	55	6.6	0.12
	i5-650	3.2	2	73	6.4	0.088
	i5-655	3.2	2	73	6.4	0.088
	i3-550	3.2	2	73	6.4	0.088
	i3-3210	3.2	2	55	6.4	0.116
	i7-720QM	1.6	4	45	6.4	0.142
	i3-2100	3.1	2	65	6.2	0.095
	i3-2102	3.1	2	65	6.2	0.095
	i3-2105	3.1	2	65	6.2	0.095
	i3-540	3.07	2	73	6.14	0.084
	i7-3540M	3	2	35	6	0.171
	i3-530	2.93	2	73	5.86	0.08
	i5-3470T	2.9	2	35	5.8	0.166
	i5-3380M	2.9	2	35	5.8	0.166
	i3-3240T	2.9	2	35	5.8	0.166
	i7-3520M	2.9	2	35	5.8	0.166
	i5-3360M	2.8	2	35	5.6	0.16
	i3-3220T	2.8	2	35	5.6	0.16
	i7-640M	2.8	2	35	5.6	0.16
	i7-2640M	2.8	2	35	5.6	0.16
	i5-2390T	2.7	2	35	5.4	0.154
	i5-3340M	2.7	2	35	5.4	0.154
	i5-3610ME	2.7	2	35	5.4	0.154
	i7-2620M	2.7	2	35	5.4	0.154
	i5-480M	2.67	2	35	5.34	0.153
	i5-560M	2.67	2	35	5.34	0.153
	i5-580M	2.67	2	35	5.34	0.153
	i3-390M	2.67	2	35	5.34	0.153
	i7-620M	2.67	2	35	5.34	0.153
	i5-2540M	2.6	2	35	5.2	0.149
	i5-3230M	2.6	2	35	5.2	0.149
	i5-3320M	2.6	2	35	5.2	0.149
	i3-2120T	2.6	2	35	5.2	0.149
	i3-3130M	2.6	2	35	5.2	0.149
	i5-460M	2.53	2	35	5.06	0.145
	i5-540M	2.53	2	35	5.06	0.145
	i3-380M	2.53	2	35	5.06	0.145
	i7-610E	2.53	2	35	5.06	0.145
	i5-2450M	2.5	2	35	5	0.143
	i5-2520M	2.5	2	35	5	0.143
	i5-2510E	2.5	2	35	5	0.143
	i5-2515E	2.5	2	35	5	0.143
	i5-3210M	2.5	2	35	5	0.143
	i3-2100T	2.5	2	35	5	0.143
	i3-3120M	2.5	2	35	5	0.143
	i7-3555LE	2.5	2	25	5	0.2
	i5-450M	2.4	2	35	4.8	0.137
	i5-520M	2.4	2	35	4.8	0.137
	i5-520E	2.4	2	35	4.8	0.137
	i5-2430M	2.4	2	35	4.8	0.137
	i5-2435M	2.4	2	35	4.8	0.137
	i3-370M	2.4	2	35	4.8	0.137
	i3-2370M	2.4	2	35	4.8	0.137
	i3-3110M	2.4	2	35	4.8	0.137
	i3-2120ME	2.4	2	35	4.8	0.137
	i5-2410M	2.3	2	35	4.6	0.131
	i5-2415M	2.3	2	35	4.6	0.131
	i3-2348M	2.3	2	35	4.6	0.131
	i3-2350M	2.3	2	35	4.6	0.131
	i7-2649M	2.3	2	25	4.6	0.184
	i5-430M	2.27	2	35	4.54	0.13
	i3-350M	2.27	2	35	4.54	0.13
	i7-660LM	2.27	2	25	4.54	0.182
	A D2750	2.26	2	10	4.52	0.452
	i3-2328M	2.2	2	35	4.4	0.126
	i3-2330M	2.2	2	35	4.4	0.126
	i3-2332M	2.2	2	35	4.4	0.126
	i3-2330E	2.2	2	35	4.4	0.126
	i7-2644LE	2.2	2	25	4.4	0.176
	i3-330M	2.13	2	35	4.26	0.122
	i3-330E	2.13	2	35	4.26	0.122
	i7-640LM	2.13	2	25	4.26	0.17
	A D2700	2.13	2	10	4.26	0.426
	i3-2308M	2.1	2	35	4.2	0.12
	i3-2310M	2.1	2	35	4.2	0.12
	i3-2312M	2.1	2	35	4.2	0.12
	i3-2310E	2.1	2	35	4.2	0.12
	i7-2629M	2.1	2	25	4.2	0.168
	i7-3687U	2.1	2	17	4.2	0.247
	i7-620LM	2	2	25	4	0.16
	i7-620LE	2	2	25	4	0.16
	i7-3537U	2	2	17	4	0.235
	i7-3667U	2	2	17	4	0.235
	A D2560	2	2	10	4	0.4
	A S1260	2	2	8.5	4	0.471
	A N2850	2	2	6.6	4	0.606
	P4 HT670	3.8	1	115	3.8	0.033
	i5-3437U	1.9	2	17	3.8	0.224
	i3-3227U	1.9	2	17	3.8	0.224
	i7-3517U	1.9	2	17	3.8	0.224
	A N2800	1.87	2	6.5	3.74	0.575
	A D2500	1.86	2	10	3.72	0.372
	A D2550	1.86	2	10	3.72	0.372
	A D525	1.83	2	13	3.66	0.282
	i5-3337U	1.8	2	17	3.6	0.212
	i5-3427U	1.8	2	17	3.6	0.212
	i3-3217U	1.8	2	17	3.6	0.212
	i7-2677M	1.8	2	17	3.6	0.212
	i5-2557M	1.7	2	17	3.4	0.2
	i5-3317U	1.7	2	17	3.4	0.2
	i7-2637M	1.7	2	17	3.4	0.2
	i7-3517UE	1.7	2	17	3.4	0.2
	A N2650	1.7	2	3.6	3.4	0.944
	A D510	1.67	2	13	3.34	0.257
	A N670	1.67	2	8.5	3.34	0.393
	i5-2467M	1.6	2	17	3.2	0.188
	i3-3217UE	1.6	2	17	3.2	0.188
	i7-2657M	1.6	2	17	3.2	0.188
	A S1220	1.6	2	8.1	3.2	0.395
	A 330	1.6	2	8	3.2	0.4
	A S1240	1.6	2	6.1	3.2	0.525
	A N2600	1.6	2	3.5	3.2	0.914
	i3-2375M	1.5	2	17	3	0.176
	i3-2377M	1.5	2	17	3	0.176
	i7-2617M	1.5	2	17	3	0.176
	i7-2610UE	1.5	2	17	3	0.176
	i5-3339Y	1.5	2	13	3	0.231
	i5-3439Y	1.5	2	13	3	0.231
	i7-3689Y	1.5	2	13	3	0.231
	A N550	1.5	2	8.5	3	0.353
	i7-680UM	1.47	2	18	2.94	0.163
	i5-2537M	1.4	2	17	2.8	0.165
	i3-2365M	1.4	2	17	2.8	0.165
	i3-2367M	1.4	2	17	2.8	0.165
	i3-3229Y	1.4	2	13	2.8	0.215
	i5-470UM	1.33	2	18	2.66	0.148
	i5-560UM	1.33	2	18	2.66	0.148
	i3-380UM	1.33	2	18	2.66	0.148
	i7-660UM	1.33	2	18	2.66	0.148
	i7-660UE	1.33	2	18	2.66	0.148
	P4M	2.6	1	35	2.6	0.074
	i3-2357M	1.3	2	17	2.6	0.153
	i3-2340UE	1.3	2	17	2.6	0.153
	i5-430UM	1.2	2	18	2.4	0.133
	i5-540UM	1.2	2	18	2.4	0.133
	i3-330UM	1.2	2	18	2.4	0.133
	i7-640UM	1.2	2	18	2.4	0.133
	i5-520UM	1.07	2	18	2.14	0.119
	i7-620UM	1.07	2	18	2.14	0.119
	i7-620UE	1.07	2	18	2.14	0.119
	A Z560	2.13	1	2.5	2.13	0.852
	A Z550	2	1	2.4	2	0.833
	A Z625	1.9	1	2.2	1.9	0.864
	A Z540	1.87	1	2.4	1.87	0.779
	A D425	1.83	1	10	1.83	0.183
	A N470	1.83	1	6.5	1.83	0.282
	A N475	1.83	1	6.5	1.83	0.282
	A D410	1.67	1	10	1.67	0.167
	A N455	1.67	1	6.5	1.67	0.257
	A N450	1.67	1	5.5	1.67	0.304
	A N280	1.67	1	2.5	1.67	0.668
	A E680	1.6	1	4.5	1.6	0.356
	A E680T	1.6	1	4.5	1.6	0.356
	A 230	1.6	1	4	1.6	0.4
	A N270	1.6	1	2.5	1.6	0.64
	A Z530P	1.6	1	2.2	1.6	0.727
	A Z615	1.6	1	2.2	1.6	0.727
	A Z530	1.6	1	2	1.6	0.8
	A Z670	1.5	1	3	1.5	0.5
	A Z520PT	1.44	1	2.2	1.44	0.655
	A N435	1.33	1	5	1.33	0.266
	A Z520	1.33	1	2	1.33	0.665
	A E660	1.3	1	3.6	1.3	0.361
	A E660T	1.3	1	3.6	1.3	0.361
	A E665C	1.3	1	3.6	1.3	0.361
	A E665CT	1.3	1	3.6	1.3	0.361
	A CE4100	1.2	1	7	1.2	0.171
	A CE4130	1.2	1	7	1.2	0.171
	A CE4150	1.2	1	7	1.2	0.171
	A Z650	1.2	1	3	1.2	0.4
	A Z515	1.2	1	1.4	1.2	0.857
	A Z600	1.2	1	1.3	1.2	0.923
	A Z510P	1.1	1	2.2	1.1	0.5
	A Z510PT	1.1	1	2.2	1.1	0.5
	A Z510	1.1	1	2	1.1	0.55
	A E640	1	1	3.6	1	0.278
	A E640T	1	1	3.6	1	0.278
	A E645C	1	1	3.6	1	0.278
	A E645CT	1	1	3.6	1	0.278
	A Z605	1	1	2.2	1	0.455
	A Z612	0.9	1	1.3	0.9	0.692
	A Z620	0.9	1	1.3	0.9	0.692
	A Z610	0.8	1	1.3	0.8	0.615
	A Z500	0.8	1	0.65	0.8	1.231
	A E620	0.6	1	3.3	0.6	0.182
	A E620T	0.6	1	3.3	0.6	0.182
	A E625C	0.6	1	2.7	0.6	0.222
	A E625CT	0.6	1	2.6	0.6	0.231