First time DS buyer. Looking at Vanquish

Sadly I won't be able to say I have a good budget. Mine will be at most $1,000. Preferably $800 and below.

First some background about what computer I have right now. I currently am using a Dell Insprion Desktop that is about 5-7 years old. It runs Windows Vista Home Premium 32 bit, and only has 3 gigs of RAM. On boot I use about 1GB of RAM and 1-2GB of a page file. I try to keep it defrayed to keep the hard drive as fast as possible. I play games like Minecraft, Garry's Mod, Hearthstone, Terraria, TF2, and sometimes Counter-Strike: Source.
Specs:
CPU: Intel Pentium Dual Core 1.8GHz
GPU: Nvidia GeForce GT610 2GB (upgraded from ATI HD2400)
RAM: 3GB DDR2
HDD: Toshiba or Samsung (Can't remember which one it is) 500GB 5400rpm
OS: Windows Vista Home Premium 32 bit
PSU: 305W?

I've hit a bit of a limit in terms of upgrading this computer mainly because of the MoBo's Pci being 1 pciex16. My current GPU uses Pcie2x16 (backwards compatible), and the computer being limited to 4GB of RAM. I get 30-60FPS on games (depends on scene complexity).

I'm looking at getting the Vanquish 1 once it just starts to constantly crash or it just dies out. In getting it I would be looking forward to a multithreaded CPU, 64 bit, a better GPU, and most of all 8GB of RAM. I'm fairly sure I'd get a much smoother interface with 8GB of RAM and not having more than half of the OS loaded onto the HDD.

One question I would ask is would it be worth it to buy it, and should I dish out another $100 to get an extra GB in VRAM and get a 1TB HDD (Vanquish 2). How much of a speed improvement would I actually see? The things I plan on doing are gaming, school work, animating and doing some rendering, and video editing.

Thanks for any advice

EDIT: I've also been wondering, could I take the old GPU out of my current PC, and put it in the Vanquish to run as the monitor GPU, and let the 750 be for gaming and rendering and such?

EDIT: Nevermind about the above. I forgot that the i3 has an internal GPU that can handle the desktop I guess. It'd probably be easier.

Edited by JacksonML - 11 Mar 2014 at 6:54pm

Yah looking at some of the videos this morning comparing the different GTX 750s actually showed a fair difference. Now I can hope this computer dies soon lol jk.

While both systems are great, and the GTX 750ti is a nice little maxwell card, when it comes to gaming, I must recommend not getting an i3 and getting an i5. i3's really aren't that well at much. They are like the Celerons from the Pentium days. If you could save up a while longer and get the Vanq 3, it would be such a huge upgrade for you. And the performance difference between an i3 and an i5 is very nice.

I personally recommend holding out and not getting anything less than an i5.