The closest I get to gaming, is to consider whether using my computer, or buying a Wii to"play" Dance, Dance, Revolution or a clone of that game.
I mainly use my system for text editing.
I've done some image editing. I'll probably do more, since I'm working on a book that will have at least 418 photographs.
I've also been asked to do some video work/editing. I don't know how much I'll be doing. If it works out, I may need a full blown AV Studio on my system.
Eventually, I'll be getting a TV Card for the system, and converting it to a Linux Media Center.
Athalon 64 bit chip. (Sorry, I don't know which one. )
I don't know what Motherboard it has.
8 GB RAM. (This maxes out the amount of RAM that can be installed on the Motherboard.)
Current graphics card: none. (Built into the motherboard, and almost as bad as the first VGA card I ever had.)
Current sound card: none. (The sound is almost as bad as that on the Apple //e.)
One PCI-x16 slot for graphics;
Two PCI slots;
Operating system: Ubuntu 8.4 (64 bit)
(I'll be upgrading to Ubuntu 8.10, when the moving company reimburses me for the damage it did to my computer --- I'm still trying to figure out how they destroyed the DVD drive, and nothing else in the computer.)
I was considering this card:
SAPPHIRE 100258-1GL Radeon HD 4850 1GB 256-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Video Card.
Until I saw this one:
SAPPHIRE 100252L Radeon HD 4550 512MB 64-bit GDDR3 PCI Express 2.0 x16 HDCP Ready CrossFire Supported Low Profile Video Card
Originally, I thought that the only difference between the two was the RAM, then saw the bus difference (64 bit v 256 bit).
There is roughly US$75 price difference between the two --- assuming the 256 bit one has not had another price drop in the last five days. (Either its price has dropped since the November Best Graphic card for Gamers article was published, or I found a vendor that undercuts whoever the article uses, to determine the price of the graphics card.)
I've read about the issues with this card on Linux, but for the most part, it looks like they only affect game playing.
Is my perception wrong? Are there other things I should be looking at?
I read the article on how to select a graphics card several times. The first time led me to discovering the 64 bit v 256 bit difference between these cards. What I can't do, is translate what that article says, into what I should be looking for, based upon I how I currently use my computer, and what I expect to be using it for.
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I found my system specs.
AMD Dual-Core Barebones Processor:
* AMD Athlon64 X2 5000+ with AMD Certified Heatsink & Fan
o Socket AM2
o 2 x 2.5GHz / 2 x 512k L2 Cache
* MSI K9N6PGM-V
o Nvidia MCP61P Chipset
o Integrated Realtek ALC883 High-Definition Audio Codec with 8-Channel Surround Sound
o Integrated 10/100 LAN
o 4 x USB 2.0 Ports
* Integrated Geforce 6100 Graphics
o Up to 256MB shared
o PCI-e x16 Expansion Slot Available
* 1GB SuperTalent PC2-5300 DDR2-667MHz SDRAM
o Max 4GB (2x2GB)
o Lifetime Memory Warranty
* 250GB Seagate Barracuda 7200.10
o 7200RPM / 16MB Cache / SATA 3.0Gb/s
* In-Win EM013 Micro-ATX
o PowerMan 350w Power Supply
o Drive Bays:
+ 2 x 5.25" External
+ 2 x 3.5" External
+ 2 x 3.5" Internal
o 1x 120mm Rear Exhaust Case Fan
o 2x Front Panel USB 2.0 ports
o Front Panel Headphone Output / Microphone Input
I bought this as a bare bones system, with the idea of adding cards to improve performance, as I could afford to buy them.(I maxed out the amount of RAM, because I've too many bad experiences with "Ram of the Month" on motherboards, to trust that it will be available the following week, let along month.)
Maybe a HD 4670 at most. It's got 4 times more stream processors than the HD 4550 (320 as opposed to 80) and it costs about $70 instead of $40. A HD 4850 has 800 processors and it's overkill for you. Just for comparison, the latest integrated video solutions from AMD have 32 processors.
Particularly as it sounds like you'll be doing paid work on this system, I'd say a primary concern needs to be that "PowerMan" PSU. It's probably just waiting to blow, taking as much of your system with it as possible. For a relatively low-powered GPU (4550, 3650, 4670, 8600GT), you don't need a big one, but get something good, like an Antec Earthwatts. A 380 would be enough now, but if you end up adding more drives (possibly in a larger case), you might need more.
As to the video card, as coozie7 says you'll need to consider Linux support.