Came across this at TechReport this am
It looks like i5 will have some nice OC headroom ( 50 % ) on an individual core - but will be limited on multi-core OC constrained by power usage.
TechReport said:COMPUTEX — We started our Computex marathon this morning by paying a visit to Intel's Francois Piednoel, who showed us a desktop PC and a notebook based on upcoming mainstream Core i7 derivatives. Piednoel also let us snap a picture of an eight-core Nehalem-EX processor in the flesh.
Let's start with the desktop PC. That system contained a quad-core, eight-thread Lynnfield CPU, and it was running some video and photo editing apps.
Piednoel noted that the "Core i5" name concocted by the rumor mill is simply off—the final product will be called something else entirely, although he wasn't at liberty to say what.
Lynnfield's biggest strengths compared to the Core i7 should be lower CPU and motherboard pricing coupled with still-strong quad-core, eight-thread performance. That said, Piednoel told us the new CPU's Turbo Boost feature will also have much greater potency than the Core i7 implementation. That means if the processor's power use stays below a certain threshold, individual cores will be able to clock themselves much higher in order to speed up single-threaded tasks.
Piednoel said we "won't believe" the gains Lynnfield sees from Turbo Boost. He didn't quote any numbers, but a secondary monitor hooked up to the system showed a live 3D bar chart of individual core frequencies. Yellow semi-transparent blocks represented jumps above the default rated clock speed. As you can see, Piednoel probably wasn't kidding:
If we count pixels in a totally unscientific way, the gain looks to be around 50-55% in this particular case. So, for a hypothetical 2.66GHz processor, that would take one core to 4GHz or perhaps a little higher. Turbo Boost can raise all four of Lynnfield's cores, too, provided the CPU doesn't go outside its power envelope.
Lynnfield's mobile cousin will also benefit from Turbo Boost (supposedly even more so, in fact). Intel showed us a running notebook PC based on that chip:
Clarksfield also has four cores and eight threads, and the Task Manager provides clear evidence of that. We wouldn't expect this to show up in particularly thin, light, or cheap laptops, though. Both Clarksfield and Lynnfield are nevertheless on track to launch alongside new matching platforms in the second part of this year.
http://techreport.com/discussions.x/17012
It looks like i5 will have some nice OC headroom ( 50 % ) on an individual core - but will be limited on multi-core OC constrained by power usage.
