Just came across this page when looking for tests to show FX 6300, 6350, 8320 and 8350 power consumption.
Scroll down and apparently the 4770K and 4670K draw more power than the 2600K and 2500K respectively. I thought the whole point was better power efficiency in Ivy and then Haswell... if Sandy overclocks much better, has lower heat output AND draws less power while only being like 12% slower, why bother getting haswell lol
Especially since you can find a 2600K on ebay for like $150-200 sometimes. Might wait until I see a good deal on a 2600k instead of going for a 6350 or 8320 like i was considering.
Haswell is much more power efficient because it allocates power when it is needed. When you are not performing heavy workloads, or when you're not at your computer, it goes into a low power state. My 4770k downclocks to 1GHz when I am browsing the internet.
The link you have provided will obviously show the power draw of Haswell under a synthetic bench. It really means nothing, because you wouldn't use that in gaming.
Other reasons to consider Haswell:
It can be found cheaper than Ivybridge sometimes (Micro Center). The motherboards are often cheaper.
The motherboards are the most up-to-date
Up-to-date instruction sets
A little more performance - not much. Sufficient performance boost if you're considering heavy editing workloads, as the 4770k can beat the cheapest sandybridge extreme 2011 chip.
In my view Haswell is much much better than sandybridge.
The link I provided shows power draw under full load, power draw from single threaded, and power draw at idle. Under full load and single-threaded load the Sandy Bridge draws less than Haswell, and it's within margin of error (within 1-2W) at idle.
I'll try to find some other tests to see if different people have gotten different results, but if this site's is true power consumption is by no means better on Haswell unless there are some in between the lines stuff (such as a light load, which would draw more than idle but less than single-threaded heavy load) where it pulls ahead of Sandy significantly.
If I can find a 2500K for <$150 or a 2600K for <$200 I think I'll jump on that. Otherwise I'll probably end up getting an FX 6350.. but I still found these results interesting
Hmmm the results seem to vary pretty significantly from site to site. Some show a 2500K drawing less than a 4670K, while some show the 2500K drawing more than a 4770K.
And on the AMD side of things, some show the FX 8350 drawing 10-15% less than the FX 8150 and one or two sites I've come across show the 8350 drawing 10% more than the 8150... I might be able to disregard that one since from every source other than that I've heard Bulldozer was much less power efficient than Piledriver.
Also some show the FX 6300 comparable to a 3820 in power draw, while some show the 6300 drawing nearly as much as 3960X... agh I'm lost. Does it vary significantly depending on the chip? Could 2 people have 3570Ks (for example) and 1 person's draws 50W while the other guy's draws 65W, both at stock? Is that why overclockability varies from chip to chip?
Full load is one of those key terms that confuses people. A graphics card pulls 300W at full load, but only 200W during gaming.
It really comes down to synthetic benchmark versus real world test.
I cannot read the article, because I am not a French speaker. There could be a large number of reasons why the results it differs from other websites.
It's not going to save you a lot of money, but it is nice to have a computer that is efficient. Haswell was very mobile-centric. They made these low power states with laptops and tablets in mind. And those Haswell laptops have a ridiculously long battery life, lasting several hours or more. They are very efficient CPUs, that cannot be denied.
Everything comes down to price. Sandybridge CPUs are still very good, and if you can get one for a decent price, I don't blame you. But looking at the platform as a whole, Haswell has much better motherboards. That's the main reason I went with Haswell. Not the low power states, I just felt it was a much more complete solution.
Chips are the same at stock. Through a process of speed binning, chips are categorised and placed at the same clocks. The differences would be found in the overclocking. Increasing the volts to make those overclocks more stable. While Haswell is a capable overclocker, it can be moody. I got mine to 4.6 without any concern. Could probably go to 4.7 or more. Some people cannot overclock past 4.2.