Pentium 5 - a Rare Look Into the CPU That Could Have Been But Never Was

Long-time Slashdot reader alaskana writes: In late 2022 it was revealed that early samples of what was to be the "Pentium 5" processor, codenamed Tejas and Jayhawk were in development and made it as far as being released to board partners for evaluation. A few of these samples made it (of course) onto Ebay and then - not surprisingly - into the hands of a YouTuber. To be fair, tech site Anandtech arguably got the first scoop on this P4 successor way back in 2004, but that story seemingly never gained much traction at that time. They wrote that Intel Prescott CPUs "could hit 5GHz+ but had huge power and temperature numbers, but Tejas was expected to clock higher than Prescott - with Intel chasing the huge 10GHz CPU clocks within 10 years between 2000 and 2011 - but it ended up not happening at all." In what was supposed to be a continuation of the "GHz is king" days of the early aughts, the Pentium 5 was in spirit a continuation of the "faster-is-better" philosophy of the P4 architecture, efficiency be damned. Speeds in excess of 7 GHz(!), and a pipeline upwards of 50 stages were rumored to be targeted by Intel, but reality (and physics) reared their ugly heads as always. WCCF Tech transcribed the remarks of Intel engineer Steve Fischer, who was involved with the project. "The thing had a pipeline depth of around 50 stages and an expected clock target at one point north of 7 GHz. I call the thing "the Death Star of processors" and half-jokingly reasoned that consumer acceptance of liquid-cooled chassis would not be a big deal." Intel kicked off Project Tejas in 2003, expected in 2004 and later pushed into 2005 after issues forced Intel to redesign the chip. Before the company could do that, the Tejas Project was shelved on May 7, 2004. In the end efficiency and parallelization was to be the rule of future CPU development, but the fact that Intel had (at least briefly) had planned on taking the P4 paradigm just a wee bit further with a true Pentium 5 is a fascinating look into the past of a future that never was to be for the venerable Pentium line.

Read more of this story at Slashdot.