I have just built a PC using old asus A7a266e m/b complete with old athlon xp1800 processor and heatsink, 512 meg ddr ram. All other components are new: case including 350 watt psu; HIS 9250 ati radeon agp graphics card, dvd rom, cdr rewriter, seagate barracuda 80 gig drive, misumi floppy drive with card reader slots. Additionally I have installed an old internal zip drive. When assembled according to manual, system powers up, all drives, fans and system light on board displayed...but no boot uo sequence, no beep or vga output to screen eizo lcd in vga mode). I initially thought it was a grapghics card issue but removed and installed in old compaq E desktop and windows xp professional had no problem installing the controller so card ok. Is this a cmos issue. I had removed cmos battery overnight and reinserted to no avail. All jumpers are set to off as per m/b manual as not using jumpers to clock processor. I have removed board, checked for cracks (there are none) and reassembled removing non existing hardware (cd rewriter, dvd rom, floppy disc and internal zip drive as well as installed LAN card and cheap pci sound card). Still nothing. Had read somewhere that it might be CMOS proplem and should short it across battery terminals but not sure if this is wise. Is this a MOBO or cpu issue. Ram reuinstalled and correctly fitted. Any help gratefully received...