1) Before looking, if both desktop/tower and HP/Dell/Lenovo/Acer/Asus, then they have bad computer cases, power supplies, and mediocre motherboards.
2) On first glance I see $430. That is below the level of "mid-gaming" and below what gamers consider even entry level gaming.
So, the Dell has HD 4400 integrated graphics, an barely adequate CPU, and requires a new power supply and graphics card to make it a gaming system. You can cross your fingers and plug in a GTX 750 card for about $100 and make it a mid-level gaming system.
The HP has an A6-5200 vs the i3-4150 so HP scores 2446 as a CPU vs 4987 so is half the CPU speed.
http://www.cpubenchmark.net/...u_list.php
http://www.videocardbenchmark.net/gpu_list.php
The HD 8400 scores 356 as the important gaming graphics and HD 4400 scores 533, so the Dell also has better graphics for gaming. Between the two is a no-brainer that the Dell is better than the HP.
Next, we look at the better place to buy, which is online at newegg.com. Sales tax delivered to California, NJ, TN. They sell 15 PCs with a proper size computer case, a reasonable CPU, and price of $380 to $480 delivered.
A system with a 4GB ram card needs a second 4GB to match your level, and that is $40
http://pcpartpicker.com/parts/memory/#Z=4096001&sort=a10&s=301600
At $470
http://www.newegg.com/...6883229619
A proper computer case, and almost double the graphics performance.
$423
http://www.newegg.com/...6883229616
An OK computer case, OK CPU, and graphics GT 720 that is 60% stronger than the Dell.
or at $440
http://www.newegg.com/...6883266602
even stronger graphics than the GT 720 system
or $460
http://www.newegg.com/...6883266542
Intel Core i5 4460 (3.2GHz)
8GB DDR3 1TB HDD
Windows 8.1 64-bit
Intel HD Graphics 4600
which is strong at all of what you want to do, even if gaming is not up to the other 3 I show.
The bottom line is the FX-6300 or i5-4460 systems at $450 and $470 are so much better than the HP and Dell, there's no way I would consider either one of them.