[Need suggestions] Best performance for a low price gaming desktop?

So my sister has been thinking about upgrading her gaming pc for awhile now but she thinks it'll be too expensive since I just paid $2.2k for mine.. so I've been looking for what I think is a good setup that has high performance for a low price so she can game/record & edit videos without lag.

Her current specs are:
Intel core 2 duo 2.33ghz, 8gb ddr2 800 ram, nvidia gtx 560 sc (the gpu is fine as it is), and some random 500gb SATA II hdd. As you can see it's really shit and to top it off she's using windows vista which slows it down even more.

What I'm thinking of getting for her:
Processor - Amd FX-8150 3.6ghz 8 cores:
http://www.newegg.com/Product/Product.aspx?Item=N82E16819103960
Motherboard - Asus sabertooth 990fx SATA 6/gbs:
http://www.newegg.com/Product/Product.aspx?Item=N82E16813131736
Memory - G.Skill sniper series 8gb ddr3 1866:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231460
Storage - Crucial M4 SATA III 128gb SSD:
http://www.newegg.com/Product/Product.aspx?Item=N82E16820148442
+ I have a genuine windows 7 ultimate 64 bit to replace windows vista

This totals to around $600 after she picks a case. Is this a good setup or should I replace anything?

 

Intel core i7 2600k gives better results than the AMD FX-8150. Maybe if she plans on recording all the games the AMD is a better choice though. But the price difference is nearly 100$ so I would definately go for AMD if she also plans on multi tasking loads.
The motherboard is nice.
1600 Mhz ram is also good enough, but the price difference isn't that big so you could go with 1866.
SSD will only speed up windows and 128 GB is too little to install your games on. But it is a better experience overall, my own PC has a 64 gb ssd just for windows/photoshop/vegas and it has been an improvement.

Getting the stuff your mentioned would be a great performance boost

I'm wondering if her PSU will be good enough, considering she probably bought a computer and upgraded the video card later.. I doubt the PSU will be good enough to support everything. But you can get a 600W PSU for ~$50 so that wouldn't put the price up that much anyways.

 

Here is why the 8150 is a terrible idea-

http://www.xbitlabs.com/articles/cpu/display/core-i7-3770k-i5-3570k_6.html#sect0

As you can see, it consistently scores well lower than the Intel cpus in gaming benchmarks. She will see a lot less frames per second than even an I5 3570k.

If you take a look at this review-

http://www.bit-tech.net/hardware/2012/04/23/intel-core-i7-3770k-review/1

You will see the FX 8150 is a lesser processor for video editing and multi tasking than even an older I5 2500k. The only time the 8150 beats it I believe is in the WPrime benchmark, and that is a benchmark which uses every core 100%, so naturally something with 8 cores will beat something with 4 cores, but even then the win margin is slim.

As for the ram, if you go down the Intel route, no need to go above 1600MHz as they can't use any higher than that.

The SSD is big enough, considering windows is about 40 gigs or so, and a game is roughly 10 each? so 8 games on it isn't bad, and you can always add another HDD later. Plus that SSD is cheap! $90 for the thing is a steal.