Computer building/upgrading questions

First of all... how much does a monitor hold me back in regards to graphics (if at all?) I currently have a Hannspree HF229H that I've been using for ~6 years now. I'm likely going to be getting a new monitor, but if I decide I want to go with a dual (or triple) monitor setup, will I be hindered by my older monitor?

As for what I'm currently looking at building:

CPU - Intel i5-4670K (not sure if I need the K version if I'm not overclocking, but might be purchasing a pre-overclocked video card)
Mobo - ASRock Z87 Extreme4 LGA 1150
RAM - 8 GB (brand unknown atm, but probably whatever is cheapest amongst Kingston, G.Skill and Corsair)
GPU - I'm somewhat torn between getting two cheaper cards for crossfire/SLI or getting a better quality single card
Single - Either Radeon HD 7970 or GeForce GTX 770
Dual - 2x GeForce GTX 660 (or maybe 760, if I feel like throwing that extra $100 into it.)

I guess my biggest questions here...
1) What size case do I need (is a mid-tower too big/small/just right?)
2) Do I need the K version of the CPU if I buy a GPU that comes overclocked?
3) Is it better to get dual GPUs now or go with the single and potentially get a second one later on down the road (as opposed to replacing both in the dual setup?)
4) What sort of power consumption am I looking at? (I know I didn't put this in the list, but I'm looking at a SSD/HD combo and will get more detailed if they tend to pull varied amounts of power. Also, likely going to get a BD-ROM.)

As for what the computer will be used for.... primarily gaming (not so much WoW anymore, but TSW, LoL, Defiance, Rift, etc.) I'm not likely going to be doing any sort of video editing or 3D modeling, so if I selected something that leans more towards that than towards gaming... please let me know.

First of all... how much does a monitor hold me back in regards to graphics (if at all?) I currently have a Hannspree HF229H that I've been using for ~6 years now. I'm likely going to be getting a new monitor, but if I decide I want to go with a dual (or triple) monitor setup, will I be hindered by my older monitor?

All the graphics card sees is a 1920*1080 monitor. An older monitor will likely have a wider bezel (frame) which means you have a larger blind spot in your multi-monitor setup if spreading the image across multiple screens (if you do this, use an odd number of screens to avoid having a bezel in the centre of the image.

To your other questions:

1) What size case do I need (is a mid-tower too big/small/just right?)

Big/full towers are massive. What I would do (and what I did) is take a tape measure, and use it to see how big the case will be. Mid-towers are usually 600mm x 600mm x 250mm. Full towers are usually a bit wider, a bit deeper and quite a bit taller.

2) Do I need the K version of the CPU if I buy a GPU that comes overclocked?

Overclocking a CPU has nothing to do with overclocking the GPU. You will see a linear increase in FPS in WoW (and other MMOs) when you increase the clock speed of the processor (30% higher clock speed = 30% higher FPS).

3) Is it better to get dual GPUs now or go with the single and potentially get a second one later on down the road (as opposed to replacing both in the dual setup?)

Both SLI and Crossfire have issues with new games. I would recommend going for the most powerful single card right now, and IF you find you need more power a year or two from now, you have the choice of getting a second GPU or getting a single new GPU. It is also going to be cheaper to buy a second good card or a brand new card than buying two cards right now. You can HD 7950s for 200-230 dollars now, Newegg had a sale with the MSI TwinFrozr 7950 for 199 dollars a couple of weeks ago. You can get HD 7970 GHz cards for 300-340 dollars, one of those can be overclocked to almost GTX 780 performance if you get a good chip (and will definitely beat a GTX 770 which costs more).

4) What sort of power consumption am I looking at? (I know I didn't put this in the list, but I'm looking at a SSD/HD combo and will get more detailed if they tend to pull varied amounts of power. Also, likely going to get a BD-ROM.)

550-650W is plenty enough for a single GPU system. If you want two GPUs I'd go up to a 750W PSU.

1) Sorry, I guess I didn't phrase my question correctly, would a mid-tower be overkill for the components I've selected (will it all fit inside the case?) I'm not worried about how much space it will take up in my apartment.

2) Ok, so the K designator on the CPU only applies to overclocking the CPU, not any other parts of the system, got it.

3) You're saying an overclocked HD 7970 beats a GTX 770, but wouldn't overclocking the 770 beat an overclocked 7970?

The 7970 has more overclocking headroom than a gtx 680, and a 770 is basically a 680 with slightly different memory chips. Both overclocked to the limit will be about the same.

A mid tower has plenty of space for dual card setups. Full towers are mostly for multiple expansion cards (2-3 graphics cards, sound card, raid card), masses of hard-drives and spectacular water-cooling (or just showing off).

What is the "GHz Edition" for the 7970 and is it worth an extra $50?

Comes with a higher stock clock speed (usually 1.05GHz (1050 MHz)) and the gpu processor is binned more selectively (higher chance of getting a good overclocker). The normal clock speed of a 7970 is 925MHz IIRC. It WILL perform a bit better than a standard 7970, it should overclock with less need for tinkering than a standard 7970 too.

Here is a comparison of the two: http://www.anandtech.com/bench/product/770?vs=768

Whether that performance difference is worth the 50 dollars is something you'll have to decide for yourself. Give it another week, you might see GHz editions drop below the 300 dollar mark with a Mail in Rebate.

Looking at my old video card and I'm wondering if the rest of my system is throttling its potential... sure it's quite a bit behind the 7970, but one of the biggest factors in why I'm looking to upgrade is that my current setup seems to take issue with Dx11 (though my 6790 should theoretically be able to handle it.)

Current system (I changed out the GPU for a 6790 and put in a 550W PSU, but otherwise it's as shown.)

Skye1013 wrote:2) Ok, so the K designator on the CPU only applies to overclocking the CPU, not any other parts of the system, got it.

Same applies to the differences between the H87 and Z87 motherboards. Z supports overclocking, so if you don't need it, get an H and save the money.

I went with an i5 4570 (non-K) and Asus H87M-E. Runs quite happily.