Why the server board?

I'm gonna say no problem with compatibility, however I'm not sure you'll be able to boot with those sticks. Its possible that your board will set them at 1066 speed and boot fine. I doubt they'll boot up at 1100, so you'll have to "overclock" them to their rated speed.

It is possible that the system won't boot, so you would need some other ram in that case.

If you buy some good quality 1066 ram, you could OC to that speed. Perhaps you are ordering the 1100Mhz ram because you believe you'll haVE MORE oc'ING headroom. To be safe I would hope you have an extra stick of ram sitting around or can be borrowed from another system.

Also, that is a rather old chipset so that's why I think you may have boot issues.