Oh, HDD= Hard drive, for some reason the price for that is not included on your builds (probably because it's no longer on stock?) so you should add that (about $40-60) to your price. In the second build the case isn't included either, so it's another $30.
Therefore, the price of both would be a lot more similar:
YOUR First build:
http://pcpartpicker.com/p/3LI8q $572.52
YOUR Second build:
http://pcpartpicker.com/p/3LIaI $Total: $508.29
I made a few modifications to the first build to make it cheaper, and it's still better than the second build:
MY build:
PCPartPicker part list /
Price breakdown by merchant /
Benchmarks
CPU: AMD Athlon X4 750K 3.4GHz Quad-Core Processor ($79.49 @ OutletPC)
Motherboard: MSI A55M-E33 Micro ATX FM2+ Motherboard ($44.99 @ Micro Center)
Memory: G.Skill Ripjaws X Series 4GB (1 x 4GB) DDR3-1600 Memory ($41.99 @ Newegg)
Storage: Western Digital Caviar Blue 1TB 3.5" 7200RPM Internal Hard Drive ($56.99 @ NCIX US)
Video Card: MSI Radeon R7 260 1GB Video Card ($118.98 @ OutletPC)
Case: NZXT Source 210 (Black) ATX Mid Tower Case ($32.99 @ Micro Center)
Power Supply: Corsair Builder 430W 80+ Bronze Certified ATX Power Supply ($44.99 @ Amazon)
Operating System: Microsoft Windows 8.1 (OEM) (64-bit) ($89.98 @ OutletPC)
Total: $510.40
(Prices include shipping, taxes, and discounts when available.)
(Generated by PCPartPicker 2014-05-17 12:11 EDT-0400)
Compared to the first build:
-I dropped from the R7 265 to the R7 260. Of course the 265 is faster, but there is a big price difference ($30-40), so that's the thing that impacts pricing the most.
-I also chose only 1 stick of 4gb of ram (like the second build) to make it cheaper, but you will want to upgrade that as soon as you can (add a second identical 4gb stick, so that it will work in dual channel).
-The processor you chose is great at this price point.
-I chose a 1TB hard disk. It will cost only a bit more ($10 more) but it will be worth it.
-I used the PSU from the second build, as it's cheaper and will be enough for your needs. I believe it's also better quality.
-I added the price for the case and the hard disk drive.
Compared to your SECOND build, this one is superior in everything. (I forgot to add a dvd burner, that would be $20 more)
This build should be quite good to play these games. What resolution do you play? 1920x1080?
Of course you won't be able to play ULTRA on new games, but it will still give you a quite enjoyable experience with nice graphics and good fps.