Intel Haswell Low Power CPU Review: Core i3-4130T, i5-4570S and i7-4790S Tested
by Ian Cutress on December 11, 2014 10:00 AM ESTHaswell Low Power CPU Conclusion
There is a clear demand for lower powered everything, as long as the performance is still there. We saw this with the MSI B85M ECO motherboard we reviewed recently, whereby as long as it makes financial sense as well it becomes a win-win.
Intel ultimately keeps its binning and testing process secret, but it is the binning process that allows them to keep high yields by a partitioning off defective cores or CPUs that do not conform to the best voltage/frequency curves. Some CPUs will fall into multiple bins, allowing Intel to sell the unit as a model that needs a boost in stock due to consumer demand. This is why some processors can perform as well as others in terms of their voltage/frequency response, but the only way to guarantee a certain level of performance is to buy the exact processor you need.
Today we tested three processors: the i3-4130T, the i5-4570S and the i7-4790S. These tackle three competitive price points on Newegg at $135, $215 and $315. This is the main reason we requested these processors in rather than others, as many S or T models end up as OEM only. The OEM only models sometimes appear for sale depending on the retailer and their own stock levels, or the region, but are not available everywhere. This is a shame, as some real gems (like the i7-4765T) are on Intel's road map.
The S processors command nothing extra over the base cost, in comparison to the premium of the K models. In terms of performance, in single threaded benchmarks (and therefore responsiveness) these CPUs performed the same as their counterparts, and our i7-S CPU was right on the money all the way through. Particularly in our gaming benchmarks, no performance was lost against the bigger models. In mutlithreaded benchmarks, there was a slight performance decrease. This means a Google Octane result down from 33512 with the i7-4790 to 31127 with the i7-4790S, a loss of 7% in exchange for the reduction in TDP, but in our gaming benchmarks the only real deficit afforded by the S/T processors was that in a few circumstances, minimum frames were lower, such as Bioshock Infinite moving from 28.0 FPS on the i3-4360 to 24.5 FPS on the i3-4130T.
With the T processors, the cut is more severe, especially for the i7 models. For our i3 T processor, we are reducing down from a 54W base component to a 35W, similar to the i7 S reductions. As a result, the benchmark numbers, while lower, are comparable to those i3 models with a potential sticker saving of 19W.
Is the power reduction worth the increase in cost? Ultimately the main use for lower power processors is for systems where heat and noise are critical junctures in the design. By using a lower power processor, the heatsink can also be smaller. This means certain office designs and machines destined for communal areas of the home are the main target points, as well as potential servers that end up locked in a room somewhere. Intel's range of lower powered Haswell processors, according to their road maps, is quite substantial, although one downfall for end users is that some of the exciting parts are OEM only.
Facebook
Twitter
RSS
76 Comments
View All Comments
MrSpadge - Thursday, December 11, 2014 - link
> lower power cpus, saves us time from undervolting and just draws less power from day one.That's not the same. Low power CPUs limit your clock sped when you need it most, i.e. under full load. Whereas undervolting delivers full performance, or in TDP limited cases even higher performance. It does cut into the OC headroom, though.
xeizo - Thursday, December 11, 2014 - link
I expressed it badly, sorry. The point is as these cpus are TDP-limited you know how much they will draw the most, and can design cooling/case etc. based on that, and in "99%" of home user cases you don't need the extra performance of 4xfull load+OC without restraints - the cpu is fast during "normal" use. Even gaming. It's not the best buy for a pure rendering box or similar though ...xeizo - Thursday, December 11, 2014 - link
Btw, I noticed at a customer they had replaced all the workstations with mini-ITX HP:s, running 4570S and having SSD:s. They felt very snappy.azazel1024 - Thursday, December 11, 2014 - link
It would be nice to see what the idle power consumption is with like setups on some of the processors. In addition it is a shame that you have dV for power consumption for the Pentium models...but there are NO performance benchmarks for them. Both of the Haswell pentiums have roughly the same power consumption of the i3-4130t, but no idea what they actually can put up in terms of performance. Also rather suprised that the older Ivy Bridge i3 has such low power consumption, but seems to average slightly better than the i3-4130t.Too bad no test of the 4MB cache and higher clocked Hasy i3-ts. That would have been interesting, as that is almost exactly what I am thinking of replacing my G1610 server with. Though realistically by the time I get around to it, I'll probably be looking at a Broadwell based server.
piasabird - Thursday, December 11, 2014 - link
A lot of the 35 watt i3 CPU's are not available for sale anywhere. Especially the Haswell with the 4 meg cache and the 4600 graphics. One question I would pose is cant you just buy a regular i3 and just underclock it to use less power?MrSpadge - Thursday, December 11, 2014 - link
Yes. XBitLabs tested exactly that and the result is the same as the S/T models. The automatic voltage-frequency scaling of Turbo does all the magic behind the scenes (i.e. lowers the voltage when you lower the clock).sireangelus - Thursday, December 11, 2014 - link
Could we have mixed amd/intel linux test? it's very interesting to see since the compilers optimize more fairly.XZerg - Thursday, December 11, 2014 - link
Ian, man - seriously you need to stop these retarded Delta charts! They are useless! To make these even worse is that you are testing low wattage cpus. the people interested in such cpus are usually interested in idle and load numbers separately. what you have has no reference point to workout either the idle or load numbers.quit with these useless charts. there are many who have agreed to this.
sweetie peach - Thursday, December 11, 2014 - link
Agreed. Also the idle and load voltages would have been helpful.BrokenCrayons - Thursday, December 11, 2014 - link
I like the review, but I agree with this. I think readers would understand that their individual results are going to be different because they won't be running identical configurations, but we can do the simple subtraction ourselves if we want to see the difference in load versus idle. I'd much prefer getting the total system wattage at idle and load from a review. It seems more useful to me to see those raw numbers actually posted.