Looking to buy/build a new budget PC

[plaguis]

Hey all, finally decided it was time to upgrade my ancient computer as it has recently started having some stability issues, and I've also taken a large interest in the MMO World of Warcraft. I've been playing at 2-5 fps during empty questing areas, followed by hard drive failures. Right now I'm using a Pentium 4 1.13 GHZ with 512 MB of RAM and an ancient 64 MB GeForce card.  Anyways, I've been looking around for a cheap cheap prebuilt computer, as it seems I'd have to spend just as much to build what I'm looking for myself (please show me if not!), and this is what I've come up with for specs so far:

AMD A55 Chipset
Processor: AMD A4-3420 Dual Core @ 2.8 GHZ, 1 MB L2 cache
RAM: 6 GB DDR3 @ 1600 MHZ
HDD: 500 GB 7200 RPM SATA (unknown brand)
Graphics: ATI Radeon 6410D (integrated APU chip)
PSU: 300w (unknown brand, I believe it's a standard ATX size)

http://www.newegg.com/Product/Product.aspx?Item=N82E16883256800

Now my first question is, would this be good enough to run some not so modern games like WoW at decent (~30) framerates in raids/battlegrounds/groups? I'd be playing at low resolution (1024x768 SD) and low graphical settings don't bother me in the least.

My second question is if the first answer is no, it's not powerful enough   I believe I can fit a different PSU in this box, although I'm not 110% if it has a 6 pin connector or what inside...any clues there? And if not would I be safe throwing an ATI Radeon 7750 in it? I know that only draws power from the PCI-E 16x slot, but I'd feel much safer doing that if I could throw a 350w+ PSU in it. Any input?

Thank you everyone for your time!

Oh, forgot to add, I'd really like to keep the budget under $350 if at all possible. Thanks again!

[Carbon Dudeoxide]

It's an okay computer. It won't run modern games on maximum graphics, but it will run them.

Here are some useful links:

CPU Comparison
http://www.cpubenchmark.net/mid_range_cpus.html

GPU Comparison
http://www.videocardbenchmark.net/mid_range_gpus.html

Your CPU clocks in at 2,135 points
GPU is at 531

These are benchmarks tests. basically - how fast can they run.

You can use those websites to compare with your current computer.

I would check out other offers on Newegg - see if you can find any better.

[Geek-9pm]

The OP could provide a clue as to his budget. It just could be that a business computer removed  from an lease would have the CPU and memory he needs, but not the Video Graphics.
Dell sells refurbished desktops with dual core 64 bit CPU and a OEM version of Windows 7. This might be more cost-effective that building from abstract. Just have to add a top graphics card.

In the USA, Best Buy is a local store that can sell such computers with a warranty.
Here is top HP model they offer.

Compare
Sale: $579.98
HP - Refurbished ENVY Desktop - 12GB Memory - 2TB Hard Drive
Model: h8-1437c
SKU: 8116065
Windows 8 64-bit
Technical details: 3rd Gen Intel® Core™ i5 processor; 12GB memory; 2TB hard drive
Special features: 1GB dedicated graphics; built-in wireless networking; Bluetooth

It does not come with monitor or keyboard.

IMHO, the SFF, Small form factor, is a bad idea. It is hard to work on and they can overheat. Get the standard size desktop.
Otherwise, I have been happy with refurbished and secondhand computers I have acquired.  Only my children  get to have new computers. I get the old stuff. 

[Carbon Dudeoxide]

The OP could provide a clue as to his budget.

He said $350 


One thing to add, it is often cheaper to build your computer from scratch, especially when you look into high-end performance computers.

That might be something to consider.