Is it possible to overclock my ram speed at all? And if so, could I overclock the 3 256MB sticks running at 266 MHz to 333 MHz so I can put a stick running at 333 MHz in a spare slot? My motherboard specs say it can handle 333 MHz. Thank you.

I wouldnt recemend it. Umm... Check your BIOS to see if you can run your 333MHz at 266MHz.

Your PC2100 (DDR266) may or may not run as PC2700 (DDR333)...it depends on the quality of your RAM. What motherboard do you have? What RAM speed settings are available in the BIOS? What CPU do you have? There are several that run at 1.8ghz...or do you mean 1800+? The socket A system performs best when the CPU bus & RAM bus are running at the same speed, so you don't want your CPU at 133mhz (266) & your RAM at 166mhz (333). What you'll have to do is experiment with your CPU clock settings until you find the max FSB both the CPU & RAM can handle while still remaining stable. We'll need to know your motherboard make/model & what CPU you have to be able to help...

I have the ASUS P4P800 and I know that it supports 333MHz ram. My CPU's (Pentium 4 Northwood A, rated at 1.8 GHz) is overclocked to 2.4 GHz with an FSB of 133*4(quad=pumped due to Intel) equaling 533 MHz.

Ohh, forgot to mention, all of the ram is made by crucial.

You have dual channel board that will run over 1100 Mhz (it supports PC4000). This is what I've done with a P4 2A in the P4P800 using only PC2100 in dual channel; 167 FSB setting 266 Mhz in BIOS, Sandra reports over 3500mb/s. You cannot choose 320mhz in BIOS, it won't boot. If you want better result use 2 or 4 memory sticks; don't use 3.

Sorry, I just woke up when I wrote earlier...I missed that you had a P4. Scratch what I wrote in response # 2 except for the 1st sentence...lol