OK. I bought an extra gig of ram, (667 mhz Corsair) which now makes it a total of 2 gigabytes composed of 4 sticks.
Upping the FSB to the usual 333 for a slight overclock of my E6300, I can't even post (let alone boot). Asus automated recovery (or whatever its called) doesn't work. I had to clear the CMOS with the appropriate jumper.
Setting manual RAM timings and freq. didn't alleviate the problem.
What's surprising - I flashed the latest BIOS version (1102) which according to relase notes - supports 4 dimms.
I got the same thing last year, oddly enough with Corsair too.
All I needed to do was loosen the timings a little bit and it flew without needing to raise the voltages. Although the RAM became more 'latent' the increased quantity made the machine faster and more responsive overall.