DDR 266 too slow for DDR333+ mobo?

Hey everyone,

So my P4 system died a couple months back, high pitched whine and random restarts. Since a brand new OCZ power supply didn't seem to fix the problem I decided my 4-5 year old motherboard was probably going, so I got a Asrock P4Dual-915GL. The mobo just arrived today and I hooked everything up and while I think the system is booting up I'm getting a black screen from the TV. Anywho, after reseating the video card with no luck, I went to the motherboard manual and noticed that it claims to only support DDR 333 or DDR 400. Unfortunately, all I have are two 512mb sticks of DDR 266.

So, my question is... will the computer be able to boot up with the DDR 266 or do I need to look into some new mem sticks?

I'll try and trouble shoot through the rest of the computer and see if something else is causing the lack of video, but I figured I'd see if someone more knowledgeable with ram would know if that could be causing me trouble.

Thanks!