The company behind the popular Geekbench software tool has taken another pot shot at Intel's BOT software.

Primate Labs says that Intel BOT "only supports a handful of applications, meaning BOT-optimized benchmark results paint an unrealistic picture of how a CPU performs in practice. This makes Intel processors appear faster relative to AMD and other vendors than they would be in typical, real-world usage."

Following the announcement last week that all Geekbench results posted courtesy of Intel's new Arrow Lake Plus CPUs would receive warning flag in the online database, Primate Labs has a new blog post detailing the results of in-house testing carried out with Intel's BOT software.

Primate Labs actually carried out their testing on a Panther Lake laptop rather than one of the new Arrow Lake Plus chips. Turns out Intel's Panther Lake CPUs also support BOT, something Intel didn't initially flag.

Anywho, Primate Labs says, "Intel’s public documentation on BOT is limited, so we decided to dig in ourselves to understand how it works and what optimizations it’s applying to Geekbench."

Primate Labs claims it discovered that BOT is going well beyond Intel's characterisation of how the software operates.

"Based on the instruction counts, it’s clear BOT has performed significant changes to the HDR workload’s code. The number of total instructions is reduced by 14%. Most of that reduction comes from BOT vectorizing parts of the workload’s code, converting instructions that operate on one value into instructions that operate on eight values.

"This is a significantly more sophisticated transformation than simple code-reordering. Intel’s public documentation only discloses the simpler code-reordering techniques, not the vectorization transformations observed here," Primate Labs says.

If Primate Labs is correct, that's certainly something of a concern. To quote myself from last week, "my understanding is that what Intel's BOT is doing essentially amounts to re-ordering instructions so that they fully utilise the Arrow Lake Plus pipeline. All the actual calculations are the same. In other words, enabling BOT doesn't mean skipping any work."

I said that based on Intel's description of how BOT works, but if Primate Labs is correct, there's quite a bit more going on. Primate Labs also found that BOT adds a time penalty to application start up. "When running Geekbench 6.3 with BOT enabled, the first run has a 40-second startup delay before the program starts. Subsequent runs are faster, with a 2-second startup delay. The startup delay disappears when BOT is disabled," the blog post explains.

Ultimately, this all comes down to how many applications end up supporting BOT. My understanding is that application support will require Intel's Labs specifically doing optimisation work and adding the results of that to the tool. Quite how many apps Intel will choose to optimise is unclear, but the fact that BOT is never going to just work with any given app is a clear negative. Primate Labs probably has a point here, therefore.

Intel recently spilled the beans on its upcoming Panther Lake CPU architecture, which seems to be an iterative improvement over previous designs, plus the promise of being built on a new process node, 18A. But in case you've wondered about some of the broader design choices that went into the last couple of generations plus the upcoming one, Intel's just answered why these CPU cores are the way they are.

Well, at least in one respect, that is, this is being why simultaneous multithreading (SMT) was abandoned. In a recent interview with Chips and Cheese, Intel's lead x86 CPU architect Stephen Robinson tells interviewer George Cozma that "SMT isn't necessarily as valuable" once you add hybrid cores into the mix.

Intel has been using hybrid cores—a mix of P-Cores for heavy workloads and E-Cores for lighter ones—for the past few years, ever since 12th Gen Alder Lake processors. Initially, these had multithreading. But the most recent Lunar Lake mobile and Alder Lake desktop chips—the first ones other than Meteor Lake to use the 'Core Ultra' nomenclature—ditched SMT altogether.

This trend is continuing with upcoming Panther Lake processors: they won't have SMT.

Robinson explains that SMT isn't as valuable in hybrid architectures because once you go hybrid, your main CPU task scheduling is sorted by designating workloads to E-Cores or P-Cores. It's only after this scheduling is done that stuff is assigned to threads: "those are the threads on top of the dessert."

So there isn't much to lose there once you've switched scheduling decisions from threads to distinct core types, but apparently there is plenty to gain: "We didn't lose a lot in client because of hybrid and the core count, but we gained a bit in our design and execution." Freeing up silicon used to deal with SMT allows the chip to be a little smaller, lower power, and hit its frequency targets a little easier:

"Now you've kind of got something that's maybe a little bit easier and less expensive and maybe can go a little bit faster." And earlier in the interview, Robinson explained: "If we can get more workloads running on an E-Core then we can bring more efficiency to the whole platform."

We already heard Intel's Robert Hallock last year explain of Lunar Lake that "our E-cores are getting so good, we can deliver better than SMT, better than Hyper-Threading performance, without Hyper-Threading." But it's interesting to hear a little more concretely why this might be the case.

Panther Lake is shaping up to be quite exciting, even if Intel hasn't reinvented the wheel with it. SMT be damned, 2026 could be an interesting time for client CPUs, including for gaming.