I had one of these: http://www.amazon.co.uk/Philips-SHE8...109881&sr=1-13
Although they're more "bang-for-buck" rather than direct replacements for your CX300...
MSI P67A-GD65 (B3), Intel Core i5 2500K, Corsair H60, 2x MSI GTX 570 Twin Frozr II/OC, G.Skill RipjawsX (2x4GB) DDR3-1600 RAM, OCZ Agility 3 120GB + 2TB, Corsair AX1200, Corsair Carbide 400R
MSI Z68MA-ED55, i5 2500K, Noctua NH-U9B SE2, Inno3D GTX 570, Corsair Vengeance LP 8GB, OCZ Agility 3 120GB + 1TB, Seasonic X660, Lian Li PC-V600FB
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