Stock Selection: Grok 4.5's picks for 2026-09-21
Grok 4.5 picked INTC, AMD, ARM, SOXX, NVDA for a 1-day horizon. Portfolio return vs SPY: +1.15%. Picks that beat SPY: 60%.
| Experiment | Stock Selection |
|---|---|
| Model | Grok 4.5 |
| Prompt version | stock-selection-v8 |
| Asked | |
| Horizon | 1-day |
| Measured from | 2026-09-21 |
| Measured to | 2026-09-22 |
| Benchmark | SPY |
| Status | Settled |
| Portfolio return vs SPY | +1.15% |
| Picks that beat SPY | 60% |
| Benchmark return | +0.57% |
The picks
| Rank | Symbol | Return | Confidence | vs benchmark | Called right |
|---|---|---|---|---|---|
| 1 | INTC | -0.23% | 62% | -0.80% | No |
| 2 | AMD | +0.33% | 60% | -0.25% | No |
| 3 | ARM | +4.77% | 58% | +4.20% | Yes |
| 4 | SOXX | +2.28% | 55% | +1.70% | Yes |
| 5 | NVDA | +1.46% | 52% | +0.89% | Yes |
The model's market view
US equities opened higher on September 21 with semiconductors and AI-related names leading as oil prices declined and Treasury yields eased. SPY traded near 767-769. Semiconductor strength from the prior session carried over, supporting selective outperformance potential in chip stocks and related ETFs over the remainder of the session.
Why each pick
INTC
Intel showed strong intraday momentum with gains of roughly 9-12 percent on semiconductor and AI optimism amid falling yields and oil. Continuation of the rebound from recent levels could allow it to outpace the broader market. Risks include profit-taking after the sharp move and any sector-wide fade if risk appetite softens.
AMD
AMD advanced approximately 8-9 percent intraday, benefiting from the same semiconductor and AI flow that lifted peers. High relative strength versus SPY supports a thesis of continued outperformance into the close. Risks are elevated volatility typical of the name and potential mean-reversion after the multi-day rally.
ARM
ARM gained roughly 10-13 percent on the session, reflecting strong demand for semiconductor design exposure tied to AI infrastructure spending. Momentum and sector leadership increase the probability of beating SPY over one session. Risks include valuation sensitivity and rapid reversal if broader tech flows reverse.
SOXX
The semiconductor ETF rose about 3 percent, capturing broad chip-sector strength while oil and yields declined. Diversified exposure to the leading group improves odds of modest outperformance versus SPY. Risks are dilution from weaker holdings and any late-day rotation out of growth.
NVDA
NVIDIA posted a smaller but positive gain near 0.7 percent while the semiconductor complex led. As a core AI beneficiary it remains positioned to participate in any extension of the session's risk-on move. Risks include already elevated levels and lower relative beta compared with more extended peers on the day.
Other models on the same run
| Model | Picks | Portfolio return vs SPY | Picks that beat SPY |
|---|---|---|---|
| GPT-5.6 Sol | AMD, INTC, META, SMCI, GLW | +0.23% | 20% |
| Claude Opus 5 | SMH, NVDA, ICHR, QQQ, IWM | +0.76% | 80% |
| Muse Spark 1.1 | GOOG, NVDA, JPM, MSFT, AAPL | -0.27% | 80% |
| Gemini 1.5 Pro | NVDA, GOOG, AAPL, SOXL, MSFT | +1.73% | 100% |
| DeepSeek V3 | AMD, INTC, ARM, MSTR, COIN | -0.04% | 40% |
Written up on ForecastNest Insights: Stock Selection: Grok 4.5's picks for 2026-09-21.
ForecastNest provides AI-generated market analysis and quantitative research for informational and educational purposes only. Nothing here constitutes financial, investment, legal, or tax advice.