At the Bradley Manning trial, prosecutors identified the laptops by serial number. So I looked up the serial number on the vendor's websites.
Bradley Manning's laptop was a MacBook with a serial number of W8939AZ066E. I went to the Apple Care support site (https://selfsolve.apple.com/agreementWarrantyDynamic.do) and entered that information. I find that it's a mid-2009 MacBook Pro, 13-inch.
I did the same with the Dell serial numbers of computers recovered from the SCIF, which turn out to be a D530 with serial number HLBJQF1 and a D820 with serial number 93H4QD1:
I find it interesting that Dell leaks the warrantee info. Note that by the time Manning used these computers in November 2010, the warrantee had recently expired.
We imagine SCIF's are super-secure rooms with powerful computers, like dramatized in the first Mission Impossible movie. What we see here is that it's actually a hodgepodge of outdated Dell laptops, in a trailer on a military base.