I've had something similar, one day when TF2 launched it had forgotten all my settings, although not quite to that extent, e.g. I still had my custom HUD, but the changes I'd made to it were gone and my launch options had disappeared. Doesn't happen every time I launch though.

Nice misquote

Afterglow

"You can't capture without having your flag at home. This prevents teams just trading caps forever and avoiding confrontation."

This was a feature of ctf_haunt, of all the problems with that maps this was quite a major one. It's easy to abuse by taking an early lead then taking the enemies intel once more and camping with it where they can't kill you. You don't even need to defend your intel at all because they can't do anything with it if you get a very strong defence around their intel. Sure it's a cheap tactic but depending on how awful the map is, such as ctf_haunt, camping with their intel until the timer runs down is often more fun than actually playing the map.

A few things to sort out: First of all, I wouldn't recommend streaming at all with that set up.

I'd ask what your internet speed is but if you're lagging at anything above 800kb/s bitrate then it isn't high enough to stream. Also, streaming at 1080p 60fps requires somewhere around 3.5-4.5k bitrate depending on what kind of quality you're looking for and streaming 1080p 60fps with a 560ti is never going to happen, especially since if you only have a 560ti your CPU is probably fairly old and not that great anyway. To put it into context, I have a 3570k at 4.3ghz with a 7970, fairly top of the line and I wouldn't dream of trying to stream above 720p 60fps, and when I did stream (when it wasn't for VTV) I streamed at 720p 30fps to reduce lag further and that was with 3k bitrate on a 6mb/s upload connection. On a connection that lags above 700 bitrate I wouldn't try streaming at anything over 480p 30fps, if that. On that particular computer, I wouldn't stream at all because it will introduce very noticeable lag when playing. Also, streaming 1080p 60fps when you don't have quality options is very much not recommended as there are very few people, especially considering the size of the TF2 community who could actually watch it. Even 720p 60fps isn't recommended if your stream doesn't have quality options.
In short, your settings are completely out of balance and you're trying to stream with a computer and a connection that are entirely unsuitable for streaming.
If you do want to fix the letterboxing on your stream try this: right click the TF2 source in OBS, go to "position and size" and then "fit to screen".

Edit: after reading Lange's post, I'd agree that while it would be possible for you to stream, I'd recommend against it if you can't deal with stuttering and higher ping.

If you definitely need firewire then sure go for the UD5H. The UD5H is about the best price/performance ratio on z87 boards anyway, but most generally don't need that overclocking performance. Given an NH-D14 however, you can actually make use of it so it isn't wasted money on features you'll never need.

The Samsung 840 Evo is the best price/performance you can get generally. Samsung, Sandisk, Adata and Kingston are all good brands, as they make flash memory so they can save the very best for themselves so they generally get the best performance and reliability. I'd definitely recommend the 840 Evo 128gb or 256gb (or the 840 Pro but it's more expensive) but if you can't find either of those, the Sandisk Extreme and Kingston HyperX are also very good drives.

Swapping out the motherboard for the UD5H really isn't worth it for the extra expense. What sound card do you have? If it's using firewire and you're looking at a ~£800 budget now, I'm assuming it isn't very modern or was quite cheap, in which case the onboard audio on the motherboard will be more than adequate. Onboard audio on z87 boards is really very good compared to old onboard audio.

As for your streaming question, I have a 3570k and a 7970, so basically the last-gen 4670k and the 280x is just a rebadged 7970 and I could stream 720p 60fps without much noticeable lag and the game was on absolutely max settings, check any VTV cast I streamed. That was using the game at 720p, but with the game at 1080p and a lower quality stream and lower quality graphics you'd be perfectly fine.
I'd recommend possibly going with the GTX770 if you can find it for a similar price however. 280x's are generally very expensive at the moment as they were all bought for the bitcoin mining hype going on and g-sync compatibility will be very useful in the future. AMD has free-sync sure, but it isn't clear whether or not displayport 1.3 (which is required for free-sync from what we know) is included on the 280x.
One other thing I'd recommend changing is getting an SSD, even if it was an SSD with no HD now and then save another £45 at later date for a hard drive. An SSD really does make a difference.

Thanks :D

I'm pretty sure the HDMI wouldn't work if it has HDCP, my brother had the problem when even converting HDMI to DVI which doesn't require any conversion for the video, the HDCP encryption can't be carried over. Maybe there are special adaptors that work with HDCP, I'm not sure. Converting displayport to DVI, digital to digital isn't easy and until recently the adaptors were still quite expensive so trying to convert it to VGA would be more difficult, and I wouldn't be surprised if DP-VGA adaptors didn't exist at all.

Since it's already been necro'd I'll just add RIP

http://www.pcper.com/reviews/Graphics-Cards/AMD-Variable-Refresh-FreeSync-Could-Be-Alternative-NVIDIA-G-Sync

An update to the free-sync business: looks like you will almost definitely need to upgrade monitor and maybe graphics card to use, unless you have a notebook that uses eDP already. Still a better solution than g-sync in my mind as it isn't a proprietary solution and supported monitors don't need to cost much more with a specialised Nvidia branded g-sync controller since controllers that support the variable refresh rate should be fairly common.

I did say the phenom has an mATX version. It will still have airflow issues, but you would just have to deal with a hot graphics card.

A good option for another case to look at is the Bitfenix Prodigy as it has the airflow that CopperSide mentioned. Whilst slightly larger than the Phenom it is still very small and you can fit your optical drive as well. However, there is also a mini ATX version available meaning you wouldn't need to change any parts, although I'm not sure if you'd be able to fit the optical drive in as the case has a pretty weird layout. You'd also definitely need to watch some build videos of it to figure out how to put it together. I'd recommend spending the money saved from not buying a new motherboard on a 128gb SSD and having a fresh install (AFTER BACKING UP) because an SSD will really make a difference. There is an mATX version of the phenom available, however I'm not sure how the airflow is for that case, and I'm pretty sure you wouldn't fit an optical drive in it.
Cheapest option I think is Bitfenix Prodigy/Phenom mATX (make sure you get the mATX not the mITX version) and an SSD, rather than the mITX version of either of those cases, with a new motherboard and potentially an SSD.

Yep, there's a thread on free-sync here http://teamfortress.tv/forum/thread/15155-amd-announces-free-sync

Not with g-sync however