Upgrading from an Intel Core i7-2600K: Testing Sandy Bridge in 2019
by Ian Cutress on May 10, 2019 10:30 AM EST- Posted in
- CPUs
- Intel
- Sandy Bridge
- Overclocking
- 7700K
- Coffee Lake
- i7-2600K
- 9700K
Power Consumption
One of the risk factors in overclocking is driving the processor beyond its ideal point of power and performance. Processors are typically manufactured with a particular sweet spot in mind: the peak efficiency of a processor will be at a particular voltage and particular frequency combination, and any deviation from that mark will result in expending extra energy (usually for better performance).
When Intel first introduced the Skylake family, this efficiency point was a key element to its product portfolio. Some CPUs would test and detect the best efficiency point on POST, making sure that when the system was idle, the least power is drawn. When the CPU is actually running code however, the system raises the frequency and voltage in order to offer performance away from that peak efficiency point. If a user pushes that frequency a lot higher, voltage needs to increase and power consumption rises.
So when overclocking a processor, either one of the newer ones or even an old processor, the user ends up expending more energy for the same workload, albeit to get the workload performed faster as well. For our power testing, we took the peak power consumption values during an all-thread version of POV-Ray, using the CPU internal metrics to record full SoC power.
The Core i7-2600K was built on Intel’s 32nm process, while the i7-7700K and i7-9700K were built on variants of Intel’s 14nm process family. These latter two, as shown in the benchmarks in this review, have considerable performance advantages due to microarchitectural, platform, and frequency improvements that the more efficient process node offers. They also have AVX2, which draw a lot of power in our power test.
In our peak power results graph, we see the Core i7-2600K at stock (3.5 GHz all-core) hitting only 88W, while the Core i7-7700K at stock (4.3 GHz all-core) at 95 W. These results are both respectable, however adding the overclock to the 2600K, to hit 4.7 GHz all-core, shows how much extra power is needed. At 116W, the 34% overclock is consuming 31% more power (for 24% more performance) when comparing to the 2600K at stock.
The Core i7-9700K, with eight full cores, goes above and beyond this, drawing 124W at stock. While Intel’s power policy didn’t change between the generations, the way it ended up being interpreted did, as explained in our article here:
Why Intel Processors Draw More Power Than Expected: TDP and Turbo Explained
You can also learn about power control on Intel’s latest CPUs in our original Skylake review:
The Intel Skylake Mobile and Desktop Launch, with Architecture Analysis
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Targon - Monday, May 13, 2019 - link
I made a similar comment, Civ6 added a new benchmark with Gathering Storm as well that is even more resource intensive. Turn length will show what your CPU can do, without GPU issues getting in the way.Zoomer - Friday, June 14, 2019 - link
Articles says that bmrk is being developed.nonoverclock - Friday, May 10, 2019 - link
Interesting article! I'm still sitting on an i7 4770 and am debating an upgrade, would be also interesting to see a Haswell i7 in the mix.HomerrK - Friday, May 10, 2019 - link
I'm one of those who bought the 2600K back in the day. A few months ago I made the move to the 9900K. Cores and price don't matter so much as feeling it will be a chip that will offer great bang for the buck for years. I think it is the spiritual successor to the 2600K and that it was a mistake to omit it.RSAUser - Saturday, May 11, 2019 - link
Not even close, it's near double the price.The Ryzen 2700 at $300 would be a way better "successor" as it's within a lot of people's budgets, offers good gaming performance and with 8 cores is probably going to last quite a while as we move to higher threading.
The Ryzen 2 chips moving to 7nm will probably have the largest leap in a while, so whichever one comes in around the $300 mark will probably be the "true" successor of the 2600K.
Targon - Monday, May 13, 2019 - link
The issue that some will have with the 2700X is that the clock speeds are not up there at the 5GHz mark, which is what many Intel systems have been able to hit for over four years now. Third generation Ryzen should get to the 5GHz mark or possibly beyond, so there wouldn't be any compromises. Remember, extra cores will only result in better performance in some areas, but single threaded and many older programs benefit more from higher clock speeds(with similar IPC).Don't get me wrong, I have a Ryzen 7 1800X in this machine and wouldn't step down to a quad-core chip again on the desktop, but I do appreciate that some things just want higher clock speeds. I expect a 40 percent boost in overall performance by switching from this 1800X to the 16 core Ryzen if it hits 5GHz, and that doesn't even count the increase in core count. I may end up paying $600 or more for the CPU though, but that will keep me happy for at least another five years.
crimson117 - Friday, May 10, 2019 - link
Finally retired my i5-2500K last spring for a Ryzen 2700X.But boy what a good run that CPU had.
jayfang - Friday, May 10, 2019 - link
Likewise only recently "demoted" my i5-2500K - still has tons of grunt as family PC / HTPCgijames1225 - Friday, May 10, 2019 - link
Same boat. I used a 2400k and 2500k for my two main PCs for years and years. Just replaced the 2500k with a Ryzen 5 1600 (they were $80 at Microcenter for some blessed reason). Tripling the thread count has down wonders for my compile times, but it's just amazing how strong and long lasting the IPC was on the 2ng generation Core i processors.qap - Friday, May 10, 2019 - link
You've convinced me. Staying with my Sandy Bridge for another year. At 1600p difference in CPU is not that high (definitely not worth 1000+ USD for completely new system) and for day to day work it is plenty fast. Up to four threads there's very little to gain and only when more threads are at play there is large enough difference (same goes for Ryzen only there I would gain almost nothing up to four threads).Perhaps Zen 2 will change that, or maybe 10nm CPUs from intel when they finally arrive with new CPU architecture and not rehash of 4 year old Skylake.