Underclocking a PII?

I have a Dell Optiplex GXa with a PII-266. The mobo has jumpers for 233, 266, 300, and 333, all with 66 MHz FSB. I happen to have a PII-350, which uses the same core voltage as a 333 but runs on a 100 MHz FSB.

So what will happen if I drop in the 350? With the clock speed only 2/3 what the chip is rated for, won't that effectively make the 350 run like a 233? This is NOT what I was hoping for, but I don't want to hack the mobo or anything. This is my firewall/router and the 266 is plenty, but 350 would be nice if it worked.

if your MB only has 66FSB, then you most likly have an LX chipset...
may have a 75 or 83 FSB option.... but since its a dell.... the jumper has probly been removed.

So your 350 (3.5x100)
will run at 233(3.5x66)

Yep, what Jay said. It will work perfectly fine and will have no problem running underclocked, ASSUMING the CPU does not have a locked multiplier. I think most of those 350 CPUs do have locked multipliers. I've heard that maybe some would run at a lower multiplier but not a higher one and some were completely locked. Guess you could try it and find out for sure. However, I'd consider looking around for a cheap used motherboard that would let you run the CPU at it's full potential.