New PSU&GPU

[Arnas]

So after realizing that at this money gaining rate I won't be able to buy a completely new rig soon enough, I decided to buy everything in two parts:
1. PSU&GPU
2. Motherboard, CPU, RAM and case.
So I finally got kinda enough money for the first step, but I am undecided on two things:
Is this PSU good enough? The rest of my parts are: an Asus M2N68-LA motherboard, 4GB of DDR2 RAM, a 500GB WD HDD and an AMD Athlon 64 X2 5000+ 2.6 Ghz processor. Also including some minor stuff like a DVD drive and a card reader.
Next, I cannot decide between GeForce 550 Ti and 560 DC. The particular models being this and this. The 560 would probably require me to wait until October, though.
Oh, and for info of the stuff I linked, click "specifikacijos". It's all in English in there.

[Schemer]

Out of the 550 Ti and the 560, definitely go for the 560. Benchmarks are far in favour of the 560.

630W is more than enough for your current setup and a 560. Brands are very important with PSUs, though, as a bad brand might not actually be a 630W, but instead (for example) a 480W that can go up to 630W without any consistency at all. I'd get a good 500W PSU, from a company such as SeaSonic, Corsair, Antec, etc. You could probably go lower than 500W with your current setup, but if you're going to be upgrading, a 500W would be a good investment.

[Arnas]

Then 560 it is.
Well, that PSU does have that 80PLUS BRONZE thing...
Looking at 500W PSUs, would this be good enough? Newegg link this time.

[Kevlar]

Their builder series is pretty much bottom end (still good though). I usually ire on the side of more watts rather then trying to get just the right amount but new video cards keep using less and less power so it doesn't really even matter anymore (stupid me bought 1200w ).

Only difference between bronze,silver,gold,platinum is how efficiently they are which just means electricity savings more or less. I think there is even a study done where it showed you only saved a few more cents every year depending on what tier. Some companies also lie to get a better rating so just do a review of that one first but that is mostly unknown name companies that you probably won't find on newegg.

[Arnas]

Hmm. Then there are two variants left:
http://www.newegg.com/Product/Product.aspx?Item=N82E16817139027 - CORSAIR Builder Series CX500 V2 500W. Seems decent enough.
http://www.skytech.lt/aeropgsstrikex500-psu-aerocool-strikex-500w-plus-bronze-active-pfc-p-78581.html This one. Couldn't find it on Newegg, though.

[Archonsod]

Their builder series is pretty much bottom end (still good though). I usually ire on the side of more watts rather then trying to get just the right amount but new video cards keep using less and less power so it doesn't really even matter anymore (stupid me bought 1200w ).

Watts don't actually matter, it's the rails you're looking at. A desktop PC shouldn't require more than a 450w supply. Ideally, you want one with at least two 12v rails, and preferably actual 3.3v rails rather than a combined 5/3v circuit.

[Belisarius]

Some PSUs will loose efficiency over time, some more, some less. A tight power fit may be insufficient 2 years gone by.

[Archonsod]

Erm, that's not how electricity works. The fan might degrade, but the actual power supply won't. At least not without sparks, smoke and flames anyway.

[Arnas]

So I'm back again.
In about 2-3 weeks, it'll be buying time for me.
So I did some catching-up and it appears quite a lot has changed on the video card market.
I was planning to get a 560 at the time I made this thread, but ever since Nvidia's 660 Ti was released, AMD significantly dropped their prices. So I pretty much settled with Sapphire's HD7870, and if I don't get enough money for that, the 7850.
Now, what I actually wanted to ask about: the PSU.
I think I should get a 600W PSU just because I'll be changing the rest of my parts later and I'd like to keep the PSU I get now.
The PSU's I have my eye on:
(sorry for the Google Translate links - the prices aren't really in pounds, but in LTL)
be quiet! Pure Power BQT L8-CM-630W
Corsair TX650M EU
These are two modular PSUs. They're obviously more expensive than regular ones, so I'll be buying them only if I get enough money.
Which one of these two are better?
Corsair TX650
NEXUS PSU 630W
These are the two regular PSUs. Again: which one of these two are better?

Oh, and also: how big is the chance my case will be too small for new GPU and I'll need to get a new one?

[Fehnor]

All of them would work fine with the possible exception of the Nexus. I'm having some trouble finding tech specs. 600W is plenty unless you want to run 3+ graphics cards 

[Splintert]

If you have an ATX motherboard you're unlikely to run out of room. mATX or smaller could be an issue.

[Arnas]

I just checked the HP site and yes, my motherboard is mATX. However, the case is Mid-size ATX.

[Splintert]

If the case is ATX, it should be large enough to hold just about anything except quad-670s.

Make sure you check, though. Wouldn't want to be partially responsible for someone having to cut a hole in the side of their case because their card is too large

[Arnas]

Alright, going to check now. I have a huuuge feeling it won't fit 
I'm back.
If I measured the correct thing, the new GPU wouldn't fit because of the HDD cage. That is, if I measured the correct thing
Anyone knows if the Nexus Prominent R is a good enough case?

[SkyTime]

Not sure if this is going to help much, but I'd go for one of those very old PC cases. The bleach white'ish grey'ish, you know.
I got one my self and it's very roomy. Could fit my rig just well, even the HD6950 Direct Cu II which is just massive.

To my knowledge they're also very cheap, not sure how easy to come by though. I have absolutely no clue what the case actually is, I just got it from a friend, but I made this epeen video to piss off King of Scotland once so you get a picture of what it looks like.

http://www.youtube.com/watch?v=T-KzYdPgpto