Upgrading my computer, advice needed

[calavera]

My current specs are

ASRock A780GXE/128M Motherboard

Athlon X2 5400+ BE OC'ed at 3.2GHZ
2GB G-SKILL DDR2 800
HD 3870

Here is what i'm looking at buying

Same Motherboard

AMD Phenom II X4 965 Black Edition Deneb 3.4GHz Socket AM3 125W $134.99

HIS H685FN1GD Radeon HD 6850 1GB 256-bit GDDR5 PCI Express 2.1 x16 $139.99

G.SKILL 4GB (2 x 2GB) 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) $54.99

For a grand total of $338.26 shipped.


I posted this at a different forum and many people told me that I was wasting my money. That I should buy a new motherboard so I will be able to get DDR3 Ram.
They said that I can get a Intel Core i3-2120 Sandy Bridge 3.3GHz Dual-Core Processor for the same price that will outperform the Phenom.

I don't do a whole lot of gaming but when I do I like to be able to run the games on a fairly high setting and my HD 3870 is beginning to show its age. I just wanted to throw in a new GPU, CPU and add a little RAM and I figured with what I selected that I would be able to run just about anything at full speed.

I figured I would get a second opinion here. So what would you recommend? I should also point out that I still have an IDE DVD Burner and my secondary hard drive. So I would either have to upgrade those components, find a new motherboard that has IDE or buy an adapter, all of which will add to the final price.

So do you think I should go all out and buy a new motherboard, or just upgrade the components. Thanks.

 

[Leeky]

You could last it out a while longer, but I'd be inclined to upgrade.

Being pedantic though, your GPU choice is not going to play every single game out there at fairly high settings, unless you're prepared to drop the resolutions.

Is your budget set in stone?

Also, what existing hardware do you have that you could reuse should changing motherboard be an option?

 

[calavera]

If I get a new motherboard the only thing I will be able to re-use is one hard drive. Everything else would have to be upgraded

 

[Ritwik7]

Under most circumstances I would save up a bit more and build an entire system from scratch. However, seeing that the Phenom II 965 is supported by your motherboard as of the latest BIOS revision (and the fact that you don't game a lot), you could actually proceed with your current plan. The 6850 would get by just fine depending on the resolution at which you play. Anything above the 1600x900 mark might seriously affect frame-rates.

 

[calavera]

Under most circumstances I would save up a bit more and build an entire system from scratch. However, seeing that the Phenom II 965 is supported by your motherboard as of the latest BIOS revision (and the fact that you don't game a lot), you could actually proceed with your current plan. The 6850 would get by just fine depending on the resolution at which you play. Anything above the 1600x900 mark might seriously affect frame-rates.

I understand the 6850 isn't a top of the line card, but considering I'm gaming with a 3870 now and it has been doing pretty good, some games have a little slowdown but for the most part it is fine. So I would think the 6850 would be a HUGE improvement over the 3870.

I am thinking about buying the video card first to see how that does with my current processor. Do you think the Athlon X2 5400+ @ 3.2GHZ would bottleneck that card?