PXE Boot taking long time to boot

I have completed 4 OSD this morning in normal time.  Now when I try to image a machine, it takes a longtime for the machine to PXE Boot.

I had been working with Dell Precision T1650 and started on the 5th and took a long time.  I tried a laptop and its doing the same thing.

1st I noticed that after selecting F12 To Network boot it was taking a while to get to the next step. Then I see

File:\SMSBOOT\boot.SDI and and it takes a while for this to load, but not as long as the Boot.wim part. This takes minium of 1/2 hour to load. 

Other offices are pxe booting just fine, but my offices is not. Any ideas?