Anandtech has a comparison of the Yonah and Merom processors from Intel – known more popularly as Core Duo and Core Duo 2 – and concludes:
Overall, Merom may not be as big of an upgrade to Yonah as Conroe was to NetBurst, but the bottom line is that you get equal or better performance in every test without increasing cost or decreasing battery life. Owners of Core Duo laptops really have no reason to worry about upgrading for now, and waiting for the Santa Rosa platform before your next laptop upgrade seems reasonable. Those looking to purchase a new notebook on the other hand have no reason to avoid Core 2 Duo models, assuming pricing is consistent with what Intel is promising. There will be a delay of at least a few more weeks as we await availability, and testing and validation by laptop manufacturers may delay things a bit more, but within the next month or so you should be able to get a Core 2 laptop.
I bought my T42 Thinkpad with a Dothan chip (ie, Yonah’s predescessor, the Pentium M). I have no regrets; I bought the T42 in December and have used it heavily. As Anand points out, the Santa Rosa platform will really give Merom it’s full potential – primarily the counterintuitive impact that increasing the front-side bus speed will have for lengthening battery life:
With Santa Rosa, clock speeds will go up slightly but more importantly we’ll get access to a faster FSB. Unfortunately a side-effect of keeping Core 2 Duo fed with a faster FSB is that while performance may go up, battery life may go down. It’ll be interesting to see what Intel can pull off with the new platform; one of the funny things about performance and battery life is that if you can complete a task quickly enough thus returning your CPU to an idle state faster, battery life will grow even though instantaneous power consumption may be higher.
Note that the other big selling point for Santa Rosa is 802.11n wireless, which promises much improved range and bandwidth. However, the 11n standard got delayed again, so the impact on Santa Rosa’s rollout is unclear. I think we won’t really see Santa Rosa until midyear 2008, which is really fine by me.
Another reason it’s worth waiting is because of storage technology. A big technological advance is perpendicular magnetic recording (PMR), which promises higher data density (and thus, more GB for the buck). Seagate has already introduced a 200GB notebook drive using PMR technology, though it only runs at 4200 rpm. Presently, you can find notebook drives up to 160GB running at 7200 rpm, so I imagine that by the start of 2008 we should see PMR drives sized 200GB and above at 7200 rpm as standard.
But more important than PMR is the new hybrid drive technology. Hybrid drives use a flash-based disk in addition to the rotating platters as a kind of super-cache. This technology is being developed jointly by Samsung and Microsoft, and Windows Vista will be heavily optimized for hybrid drives, for both performance boost and longer battery life.
Overall, notebooks in 2008 are going to have a lot of these “incremental” seeming changes under the hood. But the net effect should be pretty dramatic gains in usability. The ultimate goal: a laptop that you can take anywhere, all day. We aren’t there yet but we will be a lot closer in 2008.