OLD PC: Maximum GPU for Asus IPIBL-LA and Intel Q6600

Thank you all for your confirmation and advice!

If I may impose upon you a bit more....

1) I'll go with the GTX 750 Ti. By all accounts - including the outstanding ones on this site - it really is a heck of an advancement. In a very odd way, then, I'm rather glad that I put this off until now. It would have been really sad to settle on a solution, say, 6 months ago, and then be kicking myself just a few months later as "Maxwell" launched.

As to which one of the 750 Ti variants, I was hoping to confirm a few thoughts on maximizing its future utility:
a) I should make sure to get one with a "display port" output, yes?
b) These do NOT make use of SLI, so any thought of adding an identical card down the road for that purpose is dead in the water, right?
c) Is there an easy way - barring physical examination of a card - to determine the manufacturer of the GDDR5 modules? I noticed that reviews of some cards - here and elsewhere - make positive mention of the fact that their modules are from Samsung. I, too, would think of that as a great positive attribute, and would certainly seek out such a card if the information is easily-obtainable.
d) Some of the cards (not the reference model) have a 6-pin power connector.
i) with an eye to future use (perhaps even overclocking), I want one of these, don't I?
ii) is the use of said connector NECESSARY to use the card? That is, if I get one with the 6-pin, could I nonetheless leave it unused for now, with the card drawing its 60W from the PCIe itself? Or does its presence dictate that it is the only way the card will draw power? (This bears on how quickly I get a PSU and, more specifically, whether I need/want modularity).

2) Speaking of the power supply beyond modularity....
a) I'm a very barebones user. The ENTIRETY of data on my current system (see above) is < 100 GB, and even then there is crap on here from my wife, etc. The Mobo, CPU, and GPU will always be the only (I believe) serious power consumers in any system of mine (an SSD is next on the list of upgrades once the graphics business is sorted).
b) I'm in love with small form factor stuff. Any upgraded components I place into my current case will almost certainly find their home in something like the Silverstone FT03 (maybe even the mini).
c) given "a" and "b", plus what I assume will be a new era of efficiency in higher-end NVIDIA cards as Maxwell spreads up the product line, would I be well off enough with a 450W PSU? I'm looking specifically at the Rosewill Capstone modular 450W model, which has support for Haswell, SLI, etc. and is listed here at Toms as an absolute best-value among anything near the middle of the PSU market. It's also currently attractively-priced at NewEgg.

3) Totally new item: I spoke in my initial post about the second step being an SSD and a new OS (likely waiting for Win 8.1 to really settle in, or even for what has been rumored as a Win 9 launch already set within the next year or so). SSDs have come down in price dramatically since their launch, apparently while I wasn't paying attention, making the worse part of the SSD/OS combination - value-wise - the OS. So the line of questioning is thus:
a) would I see a performance bump of any kind by sticking with my current system (apart from the GPU and PSU) and OS (Vista 32-bit) but switching over to an SSD? Or is this precisely what you were saying my copy of Vista will NOT do, coozie7?
b) I've been reading since my original post and your replies - and this is likely a case of a little knowledge being a dangerous thing, which is why I'm grateful for this place and you all - and I've come to wonder if I would see any gain/benefit from installing an SSD alongside my normal HDD to use exclusively for gaming, and running them via WINE and Linux Mint. I've always preferred a simple OS (I used XP on another machine until its dying day, and indeed still use it in the office for strictly-offline purposes), and am old enough to have learned some DOS, etc. The command prompt system doesn't scare me. LOL. Thoughts?
c) Given the other hardware involved, would such a move (to the SSD and a Linux 64-bit OS) make going from the current 4 GB (3GB recognized) of RAM to the available 8GB worthwhile? Further, would this be futile/wasteful in terms of future use, since the best RAM this Mobo will take is DDR2-800?

I'm sorry for going into such detail, which I'm sure seems like picking nits or swatting blindly at a pinata to the well-versed. However, money is always of importance, and by nature I just hate - even if it's free - anything not having a future use and/or being grossly more capable than the current task at hand demands.

Again, thank you ALL!

Best,

Patrick