FSX used to be one of my favorite offenders but there are some more annoying and much more recent titles.
Planetside 2 takes every spot on the podium. It's multithreaded in a near completely useless way because they chose an engine where the heaviest load can only be a single thread. What could possibly go wrong there? I took my X6 down to an X3 and lost no performance(30fps in large battles either way). Then I took it to an X2 and still averaged about 30fps but with some infrequent stutters. So I posted the result on their forums and they responded(privately) saying that the big load is a DirectX9 limitation(Hint: PS2 is dx9 only). So you get Sandy/Ivy Intel users with their big IPC performance saying the game runs fine and it's AMD's fault that their product is garbage. But will Sony tell them the real reason? Nope.
Skyrim seemed to dislike my 4.7Ghz FX-6100 in built up areas or near small forts. It was a noticeable slowdown. However I saw discussions about x87 and thread checking neither of which mean much to me but the arguments seemed logical and the Skyrim x87 fix was helpful.
Here is what I'm talking about. I was up on a cliff where I could look around within about 300 degrees and get a very high FPS count(CPU bottlenecked but it was like 120fps so no big deal) but there was a tiny fort and looking near it would drop my FPS to 40 and under with noticeable small stutters. Not AMD's fault, but annoying.
World of Tanks isn't too demanding but it is too demanding for 1 AMD core if you want foliage and grass settings turned up. Once again this fuels the Intel>>>>>>AMD argument even though using 1 core for the game is the real issue. Some maps aren't so bad and the new maps are focusing on using the GPU to assume more roles but there are still 2 maps that make me want to buy a 3570 or even a little i3.
Other games that suffer poor performance from poor development include X3, NFS Hot Pursuit(2008 ish?), some areas in Borderlands 2(console ports yay!), and I know I'm forgetting or haven't played a few more because I've had to comment in threads where people don't recognize the issue(usually MMO games and console ports).
Anyway, I just feel the need to point these out on these forums when I get the chance because there are some members that really believe CPU's are insignificant. There are quite a few exceptions and if you like to play a wide range of games you will find them. This still hasn't stopped me from thinking about getting a 6300, but the more bad experiences I have with poorly optimized titles the more I think about going Intel. I'm just not sure if I think the price difference is worth it quite yet....but with their frequent mini-upgrades maybe I can get a used 2500k for 6300 money
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