What kind of budget build is that? You're emphasizing the wrong thing. His brother is gaming - which demands more GPU power rather than CPU power.
Here's a semi decent one.
Code:
NCIX Bundle Deal Intel Core i5 2500K Quad Core Processor & Gigabyte Z68XP-UD3 Motherboard $359.99
1 x Intel Core i5 2500K Quad Core Unlocked Processor LGA1155 3.3GHZ Sandy Bridge 6MB
1 x Gigabyte Z68XP-UD3 ATX LGA1155 Z68 DDR3 2PCI-E16 3PCI-E1 2PCI HDMI SLI SATA3 USB3.0 Motherboard
1 x FREE Blazing Angels (PC Game - OEM DVD-ROM) ** Intel Promo Bundle Only **
OCZ FATAL1TY Series 750W ATX 24PIN SLI Ready Modular Cables 135mm Red Fan 80+ Bronze Power Supply $84.99
2x Corsair XMS CMX4GX3M1A1600C9 4GB 1X4GB DDR3-1600 CL9-9-9-24 DIMM Memory Module $49.98 total
Visiontek Radeon 6950 2GB DDR5 2XMINIDP 2XDVI PCI-E DIRECTX11 Video Card $259.99
Deus EX: Human Revolution PC Game Electronic Digital Download Coupon *AMD Promo Only* $0.00
Zalman Z9 Plus ATX Mid Tower Case Black 3X5.25 1X3.5 5X3.5INT No PS W/ Fan Controller & Temp Display $57.98
LG Internal 22X SUPER-MULTI Drive Black Pata OEM $18.99
Hitachi Deskstar 7K3000 2TB 7200 RPM 64MB Cache SATA3 3.5IN Internal Hard Drive OEM $99.99
YOUR TOTAL $931.91
There can still be extra savings had by price-matching, and picking a different motherboard other than a Z68 unit. Also, a smaller HDD. No OS or assembly included. All prices from NCIX.
I went with the Hitachi because it's almost as fast as a WD Black, and has twice the space - I use one myself in conjunction with my SSD.
The Z68 board will enable SRT in the future for performance improvement.