C2D oc's running w/ 1 core disabled

ok i made a neat little discovery tonite , i was testing my cpu (2ghz C2D Merom T7300) using Intel Thermal Analysis Tool which shows you cpu temps and speeds in real time and allows you to load your cpu to 100% for testing, 1 or both cores, anyways i found out 2 things,

1) if loading both cores at the same time, the cpu automatically downclocks to 1600mhz from 2000mhz when hitting 100c (might be 98-99, but it looked like exactly when it hit 100 to me), which takes only about 30 seconds on my tiny laptop, so ok thats understandable, when only loading 1 of the cores to 100%, both cores heat up equally but they dont reach the critical throttle temp (they run about 80c with 1 core fully loaded) , even with my lappy, which was my worry that my cpu was auto-throtting itself when im playing CS, i guess its not, it just sucks ( OR maybe in CS it DOES downclock since the TAT only loads the CPU which doesnt take into account the GPU which is also hot during gaming? i have x3100) im thinking that might be the case, ill test them together next just have to find a program (suggestions?)

2) this surprised me, when disabling the second core in BIOS, and running the same test the cpu defaults to 2200mhz (its a 2.0 stock), and stays at 2200mhz at 80C for me, i kept running the test for over 15 minutes on 100% load and it never downclocked to 2ghz, this is the part that id like explained to me, i heard that the Penryn's have some auto-overclock feature but i didnt know the Meroms did, can someone give the lowdown on the turbo-boost? im only going to run the thing in core solo mode now, 200mhz is a decent boost, im guessing it cant do it in dual core mode because of the extra heat the second core generates is too much to overclock the core, but in single core the heat is low enough to do it?

thanks, sorry its so long

 

200MHz is not a decent boost if you have to kill one core of the processor. You are effectively removing 40-50% of the processor's ability to compute.

Sure, maybe a single threaded application will benefit...by at most 5-10%. Assuming that no other CPU intensive threads are running. And assuming the processor is the functional bottleneck of the program (that is rarely the case). If there is another thread that needs time, your main process (exe) isn't going to run that fast then. In other words, dual-core machines are mainstream and top performers for a reason.

That's the big thing with dual core...you can continue working at the speed you paid for without background tasks hogging the action.

 

Your 2) Is called Intel Dynamic Acceleration and is a feature of the Santa Rosa chipset and compatible CPUs. See here, for example.

In real life performance it is as easy to observe as the elusive sub-atomic particles since it is rare for one core to be idle for long enough for the IDA to cut in and stay running long enough for you to see.

John

 

nvm you answered my question before i replied

quick follow up: would a T9500 2.6 overclock to 2.8 then?

btw, your right that in dual core mode your not going to see it 'dynamically accelerate', it doesnt on mine just stays on 2000 or drops to 800 , i was wondering if the cpu is actually a 2.2ghz but in order to have 2 of them running on a single die and not overheat they clock them down 200mhz?, basically the same cpu design sold as a core solo would be sold as a 2.2ghz ? i know they dont sell these in solo versions, just wondering..i dont know if anyone has answers to this lol