My current build will just barely play SC2 in single player, haven't tried multiplayer yet... :-(
Multiplayer and single player are very different in requirements. Most of the very intensive graphics options won't apply in multiplayer like indirect shadows and AA, and there's also a lot of custom textures in single player that aren't in multiplayer.
I don' tknow what your current PC is, you need to fill out your specs, but there's a big difference in the two.
I could afford the I5 (still over budget, though..), but that would force me to skimp on everything else and go with a low-mid GPU, like HD7770 or GTX 650TI = poor GPU performance, if I would run other games than SC2 (I guess..?)
Yes, then you'd rather skimp on everything else. You'd literally be better off with an i5, no graphics card at all and a cardboard box, for an SC2 build, than anything else.
An overclocked i5 even, will struggle to stay above 40 minimum fps in 1v1; it's just the nature of the game, it's extremely cpu intensive and doesnt care about how many cores you have, only the strength of 2 of them, so ie a 5ghz i5 locked as a dualcore will outperform a 3990X with 12 cores at 5ghz. Believe me when I say, you really don't need much in the way of graphics at all. This game was made 3 years ago, and it was in development for what, like 7 years? That means it's based off hardware from 10 years ago, the graphics really isn't intensive at all.
Here's a vod of me streaming on medium with integrated graphics on an i7-3770k @ 5ghz:
Obviously, integrated graphics sucks, but as you can see even on medium graphics it's still doing very playably. A 7770 or 650TI is literally overkill for SC2. This isn't crysis3 here, it's an old game that was never very graphics intensive to begin with. My GTX460 768mb was able to max out all settings on SC2 easily, and my 7950 literally is the exact same FPS as my GTX460.
Because the game is CPU bottlenecked, not GPU bottlenecked. If you are concerned about running other games, then you need to understand that the more you try to focus on 'other game' performance, the worse your SC2 performance is going to be. Furthermore, an i5-3570k 4.5ghz is just 2-3x as strong as anything else out there... it'll help in many other games as well. It'll also be good enough for you to stream your gameplay, a big plus.
Maybe the GPU is a bit overkill, only thought it would be good to have a nice GPU, should I throw some more demanding games on it... At least I would like to have either a nice CPU or a nice GPU..
You need to LISTEN. I've built many, many computers for sc2, I have a high profile stream, I do a lot for sc2. You NEED an i5 to play sc2 well. If your budget is tight, you can go with a Phenom X4 (dont get an i3...), and it'll play sc2 well, but an i5 will be a good 2-3x times better for only 2x the price, it makes a huge difference.
You dont have the budget for both a good CPU and GPU, so for SC2, you need to get a good CPU. Get an i5-3570K, a Z77-D3H, 2x2gb of RAM, just a 128gb SSD, cx430, nzxt source 210, and then get a 7750, or a 7770 or 650ti boost if you can afford it.
you could also try to find a gtx 460 1GB on ebay or something, if you can find it for cheap, that'd be great. It performs the same as a 7770/650TI Boost. If you can't afford that, a GTX 450 would be able to max out the game just fine, it'll be at the cusp of "able to max out the game and have high forced AA on still"
But if I should go with a I5-3570K, I would really, really have to skimp on everything else.. And that just seems like putting all of your eggs in one basket.. On the other hand, I was always planning on going with a build, that would need to be upgraded sometime in the future.. I guess my initial thought was to go with a cheap CPU and a nice GPU, as I can get a G2020 or a Phenom II X4 965 for 70-106$.. It wouldn't be that much of a waste to swap it for an I5 in the future, whereas a 7770 of a 650TI would set me back something like 175$.. And then I would have a GPU, that would also need an upgrade, but it would have been so expensive, that I would want it to last for at least some years...
It's what starcraft 2 is. It's all about CPU. Games only care about 2 things - your CPU and GPU. They really don't care for much else. SC2 in particular is extreeeemely CPU intensive. If you are playing other games, then tell us what games they are. For an sc2 focused build though, you really need to get an i5. You can always upgrade your GPU when you play some new game after some time.
Going with a cheap CPU, and then upgrading in the future, isn't really a great idea, because then you have to upgrade the motherboard to. Sure, you could just throw an i5 in your current board, but you either won't be able to overclock because you bought a cheap i3 board to save money, or conversely, you bought an i3 with an expensive motherboard, so you won't have a good graphics card, rest of system, etc. Does that make sense?
Seriously, SC2 does NOT require much in the way of graphics at all. As I linked in the above video, having no graphics card at all can handle Medium. A 7770 or 650TI would be absolute overkill for SC2, and you can find the similarly performing GTX460 for much cheaper if you know where to look. Those GPUs will still be half decent at most games, and you can always upgrade your GPU easily in the future. You can't exactly upgrade your CPU as easily.
It would actually be much harder to swap for an i5 in the future... like I said, either you're gonna have to spend a considerable part of your budget today on a motherboard that you won't utilize at all in the hopes you one day upgrade to an i5, or you're going to have a cheap motherboard for your i3 which won't do anything for your i5. Graphics cards, on the other hand, don't care what CPU or motherboard you are using.
Seriously. Go to Teamliquid.net, and go ask in the Tech Support thread:
All these people do all day is tell people how to build starcraft 2 computers, and most of them are in europe. They will all tell you, an i3 is a waste and will struggle to play sc2, while an i5 will do a great job. If you have to go with an i5-3570K and then can only get a 7750, that's perfectly fine, you'll max out the game easily and play smoothly. But an i3 and a 7990, will struggle to play sc2 on a decent level just in 1v1. I5,i5, i5.
Cheap CPU + nice GPU = Won't be able to play SC2
Nice CPU + cheap GPU = Will max out SC2 easily
As I said:
i3 + 7990 = will struggle to play
i5 on integrated graphics = will play on medium very well.
i5 on a cheap graphics card = will max out sc2 easily
Understand this: CPU is for minimum FPS, which is very important. It's the ability to micro in big battles, to move around the map quickly without stutter, to jump to any point base or army without lag.
GPU is for graphics settings.
So an i3 + 7990, will be around 25fps most of the game. It'll be at 25fps on low graphics, it'll be 25fps on ultra graphics. Because you got the 7990, you can max out the game - the graphics isn't any impact to the CPU, but what difference does that make if your CPU is too weak?
But an i5 + 7750, will be around 60fps most of the game. It'll be at 60fps on low, it'll be 60fps on ultra. Because the 7750 is strong enough to max out the game.
you NEED an i5 to play sc2 on a good level. Even an i5 will struggle to stay above 60fps the entire 1v1 game. It's useless to put money towards a graphics card if you can't even stay above 60fps. It's just the kind of game SC2 is.
Here's a stream of me playing on ultra graphics on a GTX460, by the way:
I'm also on an i7-3770k @5ghz and 2400mhz RAM, and streaming takes a huge chunk of CPU power, and you can see just in this vod I dip to 80fps in a small