PowerConnect 2724 -- slow network -- what should I do?

I just installed a new 2724 in a datacenter.  I am running it unmanaged for now, but the network is slower than it should be (about 4 times slower on downloads).  I've use this datacenter before and their speed is typically good, so it's probably not on their side.  But I am not sure where the problem lies or what to check for.  What could be wrong, and how should I troubleshoot?  Maybe a negotiation or collision problem? I could turn on managed mode but being a novice network person I don't know what settings to adjust.

 

Thanks,

Dan