For R5400 I can get you the Gigabyte GA-P35-DS3R which is not bad for overclocking as far as I know, as well as either the Q6600 or E6850 and 2x1GB Team Xtreem Dark Ram with Heatsink DDR 800 4-4-4-12 ...
GIGABYTE "S Series" P35+ICH9R Chipset Socket LGA 775 @ FSB 1333 - For Pentium®, Pentium®D & Core™2 Duo & Quad
1 x 16X PCI-E 3xPCI Express 1x slots 3xpci, 4xDDR2 1066 (Dual) ,8x Sata2 RAID 1x ATA 133, 8x USB 2.0, SPDIF Port, Realtek 8111B GBE LAN
Durability 2 Series - All Solid Capacitors, 8 Channel High Definition Audio, Features Gigabyte SPEED, SMART and SAFE Technology
Otherwise for R5000 instead of the Gigabyte board, I will give you the Asus M-P5K:
ASUS Intel P35 LGA775, 1333FSB, 4xDual DDR2 1066, 2x PCI-x16, 1xPCI-x1, 3xPCI, 1xATA133, 4xSATAII, Gbe Lan, 8ch-Sound, Max 12xUSB, 2xIEEE1394, ATX
I'll let you know how much the OCZ ram is when I get a pricelist ... hopefully tomorrow