Im not familiar with Bios settings much. I would try to contact Intel for support of the processor, or the vendor of your motherboard.
In most cases the vendor of the motherboard posts jumper settings you can change to increase system speeds which the bios will detect without increasing multipl in bios settings.. Process of overclocking, often referred to as P.O.O, I wouldnt perform.
If your chip was disigned for 1GHZ then by all means run it at 1GHZ, make sure you have proper heatsink/cooling fans on it. I found a few repair shops lately selling people cooling fans for 233mhz computers and installing them on 2.6ghz computers, thus melting, or destroying the fan or processor entirely. P.B.O /Processor Burn Out...
You will need to see what the original settings should be on the chip design. Before you do anything contact one of those two companies they can surely say for sure what is safest to do. Some chips do not run as efficently at higher speeds, i always leave a 20 percent decrease on my systems, that way they dont run at 100 percent all the time. Also remember you can upgrade your BIOS, some are flashable. lol "I dont recommend that", but is an option, and you purchase new ones which offer more settings for cpu detection.
Sincerely,
Joe Christian