Hi guys, just signed up @ techpowerup.
Sorry for this long post coming up ...
I've started PC gaming late 1991 with a 386SX and since then I am hooked to PC hardware/software(games)/overclocking and have built a lot of systems since I had the chance to do so in my dad's company and for many friends (mainly the gaming aspect) and now I even work as an IT engineer at a company for more than 13 years.
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Shambles1980
What's a "Pentium 4 486" you mentioned twice? I know a 486 (early to mid 90s) and a Pentium 4 (early 2000s).
And you were comparing a Pentium D and a Q6600 as "4 cores. and them being actual cores using a proper architecture and not just 2 pentium 4 cores glued together". That's not really true. Yes a Pentium D is just two Pentium 4 cores together and a Core 2 Duo is a true native dual core, but a Core 2 Quad is again just a "glued together" Core 2 Duo. AMDs Phenom was the first true native Quad Core for the end customer market.
Back to the Topic ...
Your problem / upgrade wish is pretty common since a lot of people I know (including myself) still sit on their old Quad CPUs (Core 2, first Core i gen and Phenom or Athlon X4) and ask themselves if they should upgrade and if what they should get. If money was no matter they would not even have such a old system in the first place and they wouldn't think twice when upgrading.
The main problem (that has been discussed over and over all around the internet) is that somehow the CPU performance increase (kind of) flattened over the past ~ 8 years. I say kind of because the IPC (instuctions per cycle) performance increased and also the core count increased in certain classes of CPUs. So why don't we see the big boost?
One thing is that the MHz of the CPUs didn't increase that much, at least not like in the days of 486, Pentium /II/III/4 and K6, Athlon. Back then the MHz doubled and tripled von generation to generation and the IPC got better. No wonder a Athlon 1400 was almost twice as fast as a 700MHz Athlon, right? Or a 486DX2 66MHz was almost twice as fast as a 33MHz. At least in some raw benchmarks where the bus speed, memory speed and other things didn't bottleneck.
The other thing is that we still have quad cores as the mainstream and performance CPUs. That shifted a little but back in early 2007 you could buy a Quad Core, okay that was high end like the Socket 2011 CPUs (6 core) now, but Quad Core became mainstream around mid 2008.
Sure if you pay A LOT you could go out and buy that 8 or even 10 core Xeon and put it on your Socket 2011 board but there is no mainstream/performance class 6 or 8 core out there (besides the Phenom X6).
And it seems like this is going to stay that way referring to latest news that Broadwell (Haswell shrink) and even Skylake (successor of Haswell/Broadwell) will still be a Quad Core for the mainstream/performance Socket 1150/1151.
So as long as we don't see more programs that benefit of more than 4 cores and no dramatic increase of MHz the performance for the regular desktop PC will not increase as fast as it did in the years of 486, Pentium and Athlon CPUs.
@Shambles1980
I don't think your upgrade was the best you could do. Okay it was rather cheap, but that mainboard IS OUTDATED with a very old chipset. It has no USB 3.0, no SATA 6GB ports, no PCI-Express 3.0, only two memory sockets, and the overclocking capability is questionable since it does not seem to support a faster CPU than the FX-8300. (so no FX-8320, 8350 ...)
Memory runs at DDR3-1333 already overclocked according to specs.
The FX-8120 isn't a bad CPU but the programs have to make good use of it. Battlefield 4 and Windows 8/8.1 seem to like the FX CPUs. But the FX-8120 most of the time get's beaten by a i3 in games.
The prices of these i5-2500K still are high even on used models because they are still very good and fast CPUs. The difference between Sandy Bridge (i5-2500K) and Ivy Bridge (i5-3570K) at same clock speed is just a few percent. And the recent Haswell (i5-4670K) at same clock speed are only like 10-15% fasten than the Sandy Bridge. And the i5-2500K was a good overclocker - so 4.5GHz can be achieved with almost every chip (and sometimes even way more). Same with the Ivy Bridge and Haswell ... so it's not like you could OC that i5-4670K to 5GHz and more.
So my advice would have been that you get a used i5-2500K or i5-3570K. Yes that would have been more expensive but you can overclock them and be happy for the next few years.
Back to the Core 2 Quad ... since I own one (even more than one) myself i know what it can do and can't. I have a Q6700 on a EP45-DS4 and a Xeon X3370 (that's a Q9650) on a EP45-UD3P. Right now I am playing around with a Xeon X5460 with a MOD on my UD3P that is a Socket 771 CPU which is a Q9650 but with 3.16 GHz stock clock.
I have the Xeons clocked at 4.0 GHz and I have no problems playing any games. Okay I use a GTX 680 which is a little overkill for this system but at least I can use the highest setting in any game. But this Core 2 Quad at 4.0 GHz can't really hold up with an i5-2500K at stock. Sometimes it is as fast but it has some FPS drops that the i5 doesn't have.
So your Quad @ 3.6 like you said if I remember right should be quite capable too, but any i5-2xxx would be way faster in any situation. And like I said since you like to overclock and could get your hands on a used 2500K or 3570K you would be out of reach for any Core 2 Quad or Phenom II doesn't matter how high you clock these. Would be sad if it wasn't the case since these i5 CPUs are a good 2-3 years younger.
The problem is the price ... Intel wants you to pay if you want to overclock. So you at least need a K model and these start at around 180 EUR where I live and still are sold for about 100 EUR used (i5-2500K for example).
A pretty good CPU is the i3-4130 that's about 90 EUR and has a good performance for that price. But as I said you can't really overclock it and in programs/games that make good use of 4 or more cores an i5 is always faster.
On the AMD side the Athlon X4 760K is a nice CPU for only 70 EUR. You can overclock it pretty easy and the boards are cheap too, but it lacks of raw power compared to the single core power of an i3 or i5. But this is another price range anyway.
Since you already made your choice and got that FX-8120 try to make the best of it. In some cases it should be faster than your old Core 2 Quad, but don't be disappointed if it sometimes isn't faster.
Since this was also mentioned, I think and hope that the current generation of consoles push the developers to make use of more cores and also support the AMD module based architecture better so that the PC can benefit of it.
EDIT:
Uh and
@Shambles1980
I really don't get your point in "I am using a 1080p monitor but run games in 1024 or 1280"?
Is it still a CRT? Then I would understand but to run a resolution below the nativ on a LCD is usually awful. So 3D games will be the same size on the screen no matter what resolution you choose, but the detail would be the highest on the nativ resolution. So I can't follow your argument in "I see them earlier if they are far away on lower resolutions".
The only thing I can think of is that you have more FPS at a lower resolution and maybe that's why you prefer it.
So again to point it out, any LCD has to interpolate the pixels to it's native resolution, so you kind of get a smoothing / antialiasing but from less details! Regular antialiasing works the other way around as well as downsampling does.