Intel’s Core i5-655K & Core i7-875K: Overclocked and Analyzed

Again, this comes in behind the i5-661, by around 250MHz this time. There’s nothing additional that the i5-655K offers over our 661 by virtue of its unlocked multipliers – at least up to this temperature. We tried various methods to squeeze more frequency and more performance out of the i5-655K, but were unable to find a better operating point than what we’ve shown here. QPI frequency is limited to around 4.8GHz on this sample, so the only way to really get the best from the chip is to keep QPI close to this level and provide a reasonable amount of memory access latency around the DDR3-2000 mark.

There is a bit of a reprieve for the i5-655K against the i5-540 however, because although the i5-540 manages 6GHz in this benchmark it scores poorly due to a maximum 23x multiplier needing a high BCLK frequency and thus a low QPI ratio to achieve this speed. As such, based upon everything we've seen here, our conclusion is that the performance of this particular i5-655K very much fits its price. There’s certainly enough on-tap to edge out the lesser i3 series in key areas, but we've not seen enough to believe they'll knock the better i5-660+ samples off the podium.