In addition to the reduced power demands of the 45nm Penryn design granting the E8400 far higher clocks than the older 65nm Conroes and Allendales, the benchmarks (in the previous article) showed noticeable advantages even when running at comparable speeds. The 45nm processor has far lower inter-core latency and three times the cache size; a good reminder that the CPU’s clock speed isn’t everything.
As it is neigh on impossible to track down the E6300 Conroe anymore, a straight dollar comparison is difficult and largely dependent on the deal you’re able to rustle up. The E6850 Conroe can be had for $200 (at time of writing) and runs at the same 3.0Ghz clock and 1333 FSB (lesser Conroes like the E6300 run at 1066) as the E8400 but only has two-thirds the cache size, and you can get the E8400, which draws 20 fewer watts and has far lower inter-core latencies, for $170. The Allenndale E4600 is available for $120, but so is the E7200 Wolfdale, which uses a 1066FSB versus the Allendale’s 800Mhz to get the clock to 2.53 gigs to the latter’s 2.4. The only reason to go with a 65nm Core 2 Duo at the moment is if your motherboard’s chipset won’t support a 45nm, and in that case, you may want to hold off on the CPU upgrade.
Note that the E7XXX Wolfdales have 3MB caches to the E8XXX’s 6MB, but that is still better than the Allendale’s 2MB cache. The 7 series Wolfdales also lack support for Virtualization Technology, as does the E8190 (the Allendales don’t have it either). Those are big compromises: the first article explained how saving money with a lower-clocked chip is a great move for an overclocker, but you can’t tweak the size of your cache or what features your CPU has. Saving a few bucks on a technology that you don't see yourself using seems like a good idea, but if that technology catches on with application developers or your needs change, you may have missed out on a chance to future-proof. On the other hand, 50 bucks is 50 bucks if you are on a budget.
Saving money by stepping down from the E8400 to the E8200 is definitely not a big saver, their costs are pretty close right now (Newegg.com lists the E8200 for a whopping dollar less than the E8400). Stepping up to an E8500 will cost $190, 20 bucks more than the E8400, but only gets you an extra 160Mhz of clock speed: a reasonable price if you’ll be running the chip stock, but overclockers can put the money towards their cooling systems and bump the clock themselves. The E8600 costs $280, the extra $110 dollars pushing your clock to 3.33Ghz, making it an expensive choice, particularly for the overclocker. Intel’s Extreme CPUs, with their four-figure price tags, certainly deserve the moniker, at least in monetary terms.
The E8400 is obviously one of, if not the best performing CPUs for its price currently available, but is it only a good choice for a new PC or is it worth digging your perfectly good CPU out of your existing rig?
At stock speeds against an E6300, yes, but if you already have a great overclock on your chip, you may not be able to repeat the feat, which leaves me on the fence in that face off. I did get a very good clock out of the E8400, leading to good benchmarks and a decidedly zippier computing experience than I had with the older CPU, but overclocking is by no means a guaranteed process (actually its pretty much the opposite). The clincher would be if you have an opportunity to use the older chip in a family members’ or other PC that will see less demanding use than your main rig, like a Linux box or Home Theatre PC. If that is the case, now is the perfect time to use your existing CPU for that project and upgrade your flagship with the E8400.
Deciding when to pull the trigger on a CPU upgrade is obviously a decision based on personal and technical variables like what equipment you already have? And if you have money burning a hole in your pocket or just burnt a bunch of money on a wedding gift for in-laws you can’t stand? If you make the decision to go ahead in the coming months however, the E8400 is the first option to consider.