Computer going downhill.

Alright so a few years ago i got a HP pavilion A6720y.(stats here http://reviews.cnet.com/desktops/hp-pav ... 3118_7-33561679.html ) For a while it worked fine although then it started to decline in framerate while gaming.
Lately i have been looking into what other people have had to say about this pc just to find that everyone says its basically a $600 piece of junk when it comes to gaming.
So now i see that the main issue is probably the graphics card however in a prebuilt computer it is often made difficult if not impossible to replace parts not made by the same manufacturer.
So my question is basically Is it even worth it to replace some parts (and if so what parts and if you have suggestions for replacements please link) or would i be better off just getting an entire new pc (also if so, please make a suggestion. my price range i would be comfortable with is anywhere under about $1000) or perhaps find someone to build a pc from different parts for me.
I am only looking for the preformance well enough to play wow on medium or so graphics at 60 fps.
Hope somebody can help me!

DarkAbyss

It says you have a free PCIe x16 slot (you might want to open it and make sure) so you could very well just put a graphics card in and likely get what you want for performance. It would have to be a graphics card that does not require an external power adapter because your power supply is only 300W, otherwise you'd have to upgrade that as well.

Here is a good option: http://www.newegg.com/Product/Product.aspx?Item=N82E16814102930

I have that card and it can get 60fps in most games at 1920x1080. Some games I have to lower the detail a bit from highest to achieve that framerate.

If you go much higher than that in graphics cards, not only would you have to upgrade your power supply, you would also need to upgrade your CPU — it is a few generations behind and would limit the power of your graphics card. And then, you might as well just build a whole new computer because you'd be replacing everything but the case and the peripherals. Would be better to give the computer to someone who could use it or try and sell it.

You could easily build a full computer for about $600 that can play every game on highest detail if you'd rather go that route.

Processor ~$130
Motherboard ~$60
RAM ~$50
Graphics Card ~$180
Hard Drive ~$40
DVD Drive ~$25
Power Supply ~$60
Case ~$50
=~$595 (+$100 for a windows license)

If you'd like help on selecting specific parts, someone else or I can help you with that.

You will more than likely be good without the power supply upgrade. You might still want to get one to be safe, but I'm not sure it would be necessary.

The maximum specs for power usage for the Phenom X4 9550 is 95W, your motherboard is probably low end because it is a prebuilt system so it can't be more than 50W, RAM will use less than 10W of power, DVD drive about 25W, the 5670s max consumption is speced at 64W, each hard drive you have will add about 15W, fans not more than 2W each, and most USB devices will consume about 2-3W with maximum usually being 10W for high power things such as charging devices.

That comes to about 275W and this is the absolute maximum. Most of the parts will not use this much power even under 100% load, you'd have to overclock them to get close to their max spec.

Either of those two look fine and are decent brands if you were to get one though. You definitely don't need 600W like your first choice.

Get the 6770 rather than the 6670 (5670 = 6670, 5770 = 6770 , AMD rebranded everything AMD when they went to the 6XXX series cards. Many of them are the exact same model as the 5XXX counterparts, just with the AMD logo and an increased first number.). The extra ~$20 or so you spend gives you a very nice boost in performance. I'm rocking a brand new build with a 6770 as the GPU, and I've been playing every game I own at maxed settings with no issues. It's not at 1080p just due to the crappier monitors I've got available, but it looks fantastic just the same.

It doesn't hurt getting a better PSU than you need now, as you can always get better hardware in the future that will require the better PSU. I've got a 700W version of that OCZ PSU you posted, and it's ~300W more than I need. But, if I upgrade to Crossfire graphics in a year or so, I'll need the better PSU.

Hope all goes well, sounds like you're going to really enjoy the build . Just be sure to get a nice heatsink/fan for the CPU. $30 seems to be a good price point for a quiet + efficient combo, this is favored by many builders, while this is what I ended up getting. It's doing great on my Phenom II X4 955 BE, though I've still yet to get some nice thermal compound on it. It's dead silent too, honestly something I wasn't expecting.

Well a few days ago i installed both parts and my computer now runs tf2 and wow on max setting beautifully! Thanks for your help once again!

Darkabyss