Overclocking
Note that Celeron processor on Conroe-L core looks very appealing for overclockers from theoretical prospective. There are a few indirect indications that this processor should overclock very well. First if all, dual-core processors on Conroe core can reach higher frequencies during overclocking if one of the cores is disabled. Conroe-L has no second core at all. Secondly, this processor boasts very low TDP, which may also be an indication of high frequency potential. Thirdly, rough estimates of the number of transistors in Conroe-L allow us to conclude that this is a relatively simple core. While dual-core Conroe consists of 291mln transistors, Conroe-L should have a little over 100mln transistors. And the simplicity of the semiconductor die is directly connected with its overclocking abilities.
However, we should move from theory to practice now. For our overclocking experiments on the Conroe-L based processor we used the same testbed as for performance testing. We used Zalman CNPS-9500LED cooler for our processor. System stability during overclocking was tested using SP2004/ORTHOS utility that has proven very efficient over the time.
Conroe-L was overclocked with the clock frequency multiplier set to 10x, i.e. we used Celeron 440 parameters as our startup value.
Note that thanks to 200MHz FSB Conroe-L based processors should be relatively simple to overclock, meaning that there will be a lot of mainboards out there that will suit for overclocking this CPU, as no extreme FSB frequencies need to be supported. Of course, we would like to hope that Celeron processors on Core micro-architecture will allow pushing the FSB frequency to 500MHz and higher, but the reality crosses over these dreams.
The thing is that by raising the Vcore to 1.6V we only managed to increase the FSB frequency of our Conroe-L based processor up to 300MHz.
In other words, this promising processor hit its maximum at 3.0GHz. Further investigation revealed that this is a true maximum for this CPU, which has nothing to do with the so-called ?FSB wall?as well as with the mainboard features. For example, when we raised the multiplier to 12x, the maximum frequency when the mainboard remained stable dropped down to 250MHz.
So, the practical tests ruined all our rosy hopes for the wonders the new Conroe-L based processor could work. They proved to overclock even worse than Allendale based CPUs, which in their turn overclock worse than the regular Conroe based ones.
However, I have to say in favor of the new processor, that the 1.5 times frequency increase is not bad at all in the end. In fact, overclockers have always liked processors like that until Core micro-architecture came out.
In conclusion to the Conroe-L overclocking investigation, I would like to say a few words about its performance. The main question is: will the owners of the upcoming Celeron processors on Core micro-architecture be able to hit the same performance level as the contemporary dual-core CPUs can offer? To answer this question we compared the performance of the Conroe-L overclocked to 3.0GHz against that of Pentium D 925 and Core 2 Duo E4300.
The numbers speak for themselves. All in all, the overclocked Conroe-L loses to the dual-core Core 2 Duo E4300 showing better results only in those tasks that are not so well-optimized for multi-threaded environments and do not require large L2 cache memory. However, overclocking allows Conroe-L to perform as well as Pentium D 925. In almost half the benchmarks this dual-core processor on the outdated NetBurst micro-architecture runs slower than our single-core hero.
In conclusion I would like to add that the upcoming Celeron processors, if overclocked, will definitely outperform contemporary Celeron D on Cedar Mill core. The thing is that 5.0GHz is the maximum frequency contemporary budget CPUs can hit today, which is only 66% higher than what we can achieve on Conroe-L. And as we have already said before, NetBurst based processors need to run at 90-100% higher clock frequency in order to catch up with Core based processors in performance.
