I upgraded a vectra 500 series from a 133MHZ to a 233MHZ MMX but it only shows 166MHZ which it the max on the jumper settings. I want to overclock it but I don't know how. I haven't installed a HDD yet but when I get it I am gonna put either 98SE or XP Home. It has 32MB Simm and I have order 4 32MB Simms for 128MB.

Exactly which model do you have? I've seen several and none would accept 128Mb ram. Skip

Even if it does "accept" 128MB, it probably only caches 64MB. See if you can find the chipset model number on the board. It'll probably be an Intel 430VX, TX, FX, or HX. If it is, stick with 64MB as the max amount of RAM. And don't bother with XP Home, that system can't handle it. Stick with Win98SE. If you want the CPU to run at 233MHz, try setting the jumpers as if it were a 100MHz CPU...that is, 1.5 x 66MHz Asus A7N8X-X 1800+ @ 8 x 210MHz 768MB PC3200 Asus A9550 128MB/128-bit Gamer Edition WinME/WinXP Pro

BTW, the only way to overclock would be if the FSB can be set to 75MHz. If you can't do that, you'll have to wait until the HDD & OS are installed, then you can try overclocking via software. Asus A7N8X-X 1800+ @ 8 x 210MHz 768MB PC3200 Asus A9550 128MB/128-bit Gamer Edition WinME/WinXP Pro

I can set the jumpers to run at 75MHZ. I have installed Win 98. How to I overclock with sowtware? What programs do I need. Thanks.