We can't really condense 64 different graphs or 11 pages of analysis and peripheral information into a short conclusion. However, we spotted several noteworthy constants in all of these graphs.
Generally speaking, AMD's Phenom II X4 processors appear to be slightly better deals than the Intel Core 2 Quad equivalents. Not only are they great performers for the money, but the Socket AM2+ and AM3 platform has a better upgrade path than Intel's soon-to-be-retired LGA775 platform. The Phenom II X3 720 is more of a mixed bag, since it's the top performer neither in single-threaded tasks nor in heavily multithreaded ones. However, the 720 is still a good middle ground between cheap quad-cores and high-end dual-core CPUs.
Also, the Core i7-920 really distances itself from other processors in multithreaded tasks, but without giving much ground to dual-core chips in other tasks. Pricey X58 motherboards and DDR3 memory make the i7-920 an expensive step up, but clearly, you're not throwing your money out the window. The i7-920's position bodes well for upcoming mainstream Nehalem derivatives (Lynnfield), provided they're not dramatically slower.We should probably give a few pointers to folks who are shopping for a new CPU right now, as well. To start off, while this article contains many useful nuggets of information, we strongly recommend you also read our system guides and performance-oriented processor reviews to get a more complete picture of the market.
If you're still unsure of what to buy, then take a step back and think about all of the applications you run. Looking at the relevant tests here should help you determine which processor can do the best job overall for the money. You'd be ill-advised to pick a CPU strictly based on our average-performance scatter plots on the previous page, because our test suite may not reflect what you'd run in your day-to-day activities. If you use your PC for nothing but games, for example, then a dual- or triple-core processor with a high clock speed may be a better investment than a part like the Core 2 Quad Q8200.
Otherwise, your processor choice should depend in large part on your overall budget. We've established that going from a cheap duallie to a decent quad-core processor doesn't break the bank when one considers the cost of an entire system. However, that doesn't mean you should allocate a disproportionate portion of cash to a fast processor and neglect other pieces like the graphics processor and memory. Our system guides should help you make that call better than this article can.