|Intel Core i7-3770K Ivy Bridge Processor|
|Reviews - Featured Reviews: Processors|
|Written by David Ramsey|
|Monday, 23 April 2012|
Page 17 of 19
Since the Core i7-3770K uses the same architecture as Sandy Bridge, the memory controller is probably the same. But nothing reveals the truth like a good memory bandwidth benchmark, in this case SiSoft Sandra Lite. Remember, this test uses the same memory and the same motherboard; only the CPUs have changed.
Perhaps unsurprisingly, the memory bandwidth scores are all within 3% of each other, which is within the margin of error for this test. Intel says that Ivy Bridge does allow the potential for much higher memory frequencies than Sandy Bridge, although as we've shown in our memory reviews, the real-world performance impact of high speed memory is minimal.
Core i7-3770K Overclocking
I admit I came to this section of the review with high hopes: Sandy Bridge CPUs are almost insanely overclockable, with late steppings of the 2600K and 2700K reaching 5GHz on good air cooling in many cases. Surely Ivy Bridge, with its lower voltage, 22nm process, and low-leakage transistors, would be even better! Since this is a "K"-model CPU, overclocking is a simple as bumping the multiplier and adjusting the voltage as needed. As with Sandy Bridge, you can set different turbo limits that will be used when 1, 2, 3, or all 4 cores are loaded; I prefer to try to hit the highest stable overclock I can with all four cores loaded.
If you were expecting the same thing I was, prepare to be disappointed. Even with a Thermalright Silver Arrow cooler, the best air cooler I've ever tested, the highest overclock I was able to reach on all cores under load was only 4.7GHz. I didn't have to increase the core voltage to achieve this.
At 4.8GHz, the system would boot into Windows and run most benchmarks, but even though I didn't increase the voltage, individual core temperatures spiked past 100 degrees Celcius and the CPU would throttle itself until temperatures came back down, so 4.7GHz was the best I could do. The 21% overclock I achieved was completely stable, although some core temperatures would still reach into the 90s, and it's not a configuration I'd suggest running for long periods of time, as those temperatures (while apparently below the throttling limit) are still quite high.
The chart below compares the normalized stock benchmark scores with the overclocked benchmarked scores.
An 18% average improvement from a 21% overclock is pretty good. However, it's likely that a late-stepping 2600K or 2700K could be overclocked to beat the overclocked 3770K, even if by only a small margin. We can hope that later steppings of the Ivy Bridge processor will yield better overclocks as Intel refines the 22nm fabrication process.