Intel Corp (INTC)

[Saturn V]

I wonder if the Intel architects found through their simulations that HT has a higher ROI in terms of ILP than adding the OOO overhead

Ihink that it could be an attempt at power optimisation.HT probably dissipates less power than the OOO circuity, and HT had a better "ROI".

Intel appears to be getting better at HT since the Pentium 4 days. Nehalem's leaked benchmarks gave a dramatic improvement with HT, which was to be expected since Nehalem has more execution resoources than the Pentium 4. However I was surprised to see the extent of the improvement even with the minimal resources of the Silverthorne.