If your running a 750 watt PSU, with your current setup, you should have no problems running any of those cards.
A video card, is kind of a "mini computer" so to speak, thats only job is to create graphics.
Core Clock. Your video card has what is known as a GPU, (graphics processing unit) its basically, a processor on the card, the core clock, is the frequency that the CPU runs at-like the 7950, has a core clock of 850 mhz
Stream processors are a difficult thing for me to explain, the more of them a card has the better. For the technical explanation of them --->http://en.wikipedia.org/wiki/Stream_processing
Your video card, like your computer, also has memory on it dedicated just to its use. Like a computer memory module, theres different types, (ddr, ddr2 and ddr3 respectively) while video memory is classified as gddr, gddr2, etc etc. That is the interface. Like computer memory, it also has frequency it runs on-higher the frequency, faster the memory. (say 800 mhz etc.) and sizes, different cards have different sizes, most of the cards I linked have 3 gigs of memory. Video cards have their own memory, so its not sharing the system memory, which boosts performance.
In an integrated video card, (one that is built into the motherboard) the graphics chip uses part of your system memory, which slows the computer performance down. With an aftermarket video card (otherwise known as a dedicated video card) like I said, it has its own memory, and doesnt use the system ram, that is "dedicated video memory"
Edited by the_patriot11, 05 February 2013 - 10:01 PM.
Primary system: Motherboard: ASUS M4A89GTD PRO/USB3, Processor: AMD Phenom II x4 945, Memory: 16 gigs of Patriot G2 DDR3 1600, Video: AMD Sapphire Nitro R9 380, Storage: 1 WD 500 gig HD, 1 Hitachi 500 gig HD, and Power supply: Coolermaster 750 watt, OS: Windows 10 64 bit.
Media Center: Motherboard: Gigabyte mp61p-S3, Processor: AMD Athlon 64 x2 6000+, Memory: 6 gigs Patriot DDR2 800, Video: Gigabyte GeForce GT730, Storage: 500 gig Hitachi, PSU: Seasonic M1211 620W full modular, OS: Windows 10.
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