Weekly Winners | Sandisk Soars 35%; Super Micro Computer Surges 28%; Seagate Jumps 20%; Western Digital Rillies 17%

This week, which stocks lagged or dragged? Weekly Winners column keeps up with market trends, helping Tigers sort out the week's hottest sectors, stock winners and important news.

Below are top 10 S&P 500 stock gainers for the week ended August 14:

Sandisk Forecasts Mid-to-High-Teens Revenue Growth Through 2030

Sandisk on Thursday said it expects revenue to grow at a mid-to-high-teens percentage rate from fiscal years 2028 to 2030, encouraged by strong ​demand amid rapid AI infrastructure buildout.

The company said the projection ‌is in line with growth in the amount of storage capacity it produces, a metric the industry calls "bit growth."

Shares of the company soared more than 35% this week. They ​have recorded an over sixfold gain so far this year, part ​of a broader rally among memory chipmakers as investors bet on ⁠sustained demand from rapid AI infrastructure expansion.

Its peers Seagate Technology surged 19.8% this week, Western Digital advanced 17.2%, and Micron Technology jumped 10.7%.

Super Micro Gives Sales Outlook That Tops Rosiest Projection

Super Micro Computer shares jumped 28% this week as the company gave a revenue forecast for the current quarter that topped analysts’ estimates, a sign the booming artificial intelligence market continues to bolster sales of the company’s servers.

Revenue will be $14.5 billion to $15.5 billion in the period ending in September, the company said Tuesday in a Supermicro Announces Fourth Quarter and Full Fiscal Year 2026 Financial Results. Profit, excluding some items, will be $1.01 to $1.10 a share. Analysts polled by Bloomberg projected sales, on average, of $12 billion, and profit of 74 cents. The outlook topped even the highest analyst revenue estimate of $13.3 billion.

San Jose, California-based Super Micro is benefiting from surging demand for gear to train and run AI tasks. The company’s servers are fitted with the Nvidia chips that have become the workhorse for the vast majority of AI data centers. Super Micro has also been working to boost margins by selling more profitable products and trimming costs.

Marathon Petroleum Stock Jumps on Fresh Hormuz Uncertainty

Marathon Petroleum stock climbed 19.2% this week as crude oil prices jumped and Iran hardened its terms for reopening the Strait of Hormuz.

Iran said a transit deal with Oman was in its “final stages” but insisted the waterway stays shut until the United States meets additional demands. The White House, meanwhile, signaled it was easing off direct talks while leaning on economic pressure instead. That standoff is exactly what has kept refining margins elevated all year, and it is why a refiner’s stock moves harder on this headline than an upstream producer’s does.

MPC Chief Commercial Officer Rick Hessling flagged this dynamic on the company’s August 4 earnings call, addressing what comes after a blowout quarter. “We do expect more volatility here in the near term as hurricane, turnaround season approaches,” he told investors.

Its peers Phillips 66 jumped 14.6% this week, and Valero gained 14.5%.