We really need a dedicated page for technologies that span all of Windows, like DirectX - I've stumbled on an early beta/rc release of directX 8.0 for Windows 2000.
The build of the main directx files is: 5.1.2258.219 built by: Lab06_N(mmbuild). The timestamp on these files is: Wed Oct 18 05:21:31 2000
According to the wiki Page Windows XP, this timestamp would place the build right before the first Beta build of Whistler, yet the nearest build, 2257 would have been compiled months earlier - Inferring that directX 8 was derived from work done on the NT 5.1 branch up through Milestone 1, and into Beta 1's timeframe.
Now, combined with the information below, collected over a year ago by my own documenting, it would appear that these files would have come along with the factory.exe build, which may have been an internal Beta 1 build, bundled with all the appropriate directX 8.0 enhancements.
From the Whistler WinPE builds, the following files and versions were found:
Whistler WinPE Build 2296.1 has:
factory.exe, 5.1.2292.1 (beta1 001018-1846)
schannel.dll, 5.1.2296.0 (beta1 001024-1150)
adpu160m.sys, 5.1.2264.1 (lab01_N(peterwie) 000824-0817) cpqarry2.sys cpqfcalm.sys sparrow.sys SYM_HI.sys sym_u3.sys symc8xx.sys symc810.sys symmpi.sys
aic78u2.sys, 5.1.2278.1 (beta1(peterwie) 000930-1744) aic78xx.sys
hpn.sys, 5.1.2284.1 (beta1(peterwie) 001008-1854) perc2.sys, 5.1.2284.1 (beta1(peterwie) 001008-1854)
Whistler WinPE Build 2462 has:
cpqarry2.sys, 5.1.2409.1 (ReleaseBinaries 001205-1804) dpti2o.sys sparrow.sys sym_hi.sys symc8xx.sys symc810.sys
adpu160m.sys, 5.1.2419.1 (Lab01_N 010116-0152)
perc2hib.sys, 5.1.2441.1 (beta2 010218-0157)
hpn.sys, 5.1.2451.1 (beta2(johnstra) 010218-0157) perc2.sys