Two companies with no product inside an artificial-intelligence server rack led the market's 800-volt power theme over the past month. Neither sells a converter, a magnetic or a power stage into a graphics-processor tray. One of them is barely a business yet.

Ideal Power, an Austin-based developer of a bidirectional solid-state switch it calls B-TRAN, recorded revenue of $5,800 in the second quarter against a net loss of $3.4m. It employs 17 people. The shares rose 17.3% over the past month, which values the company at roughly 2,660 times trailing sales — a number that means nothing except that revenue is not the thing being priced. What is being priced is a $400m sales "pipeline", split about evenly between automotive and data centers, and a co-developed intelligent circuit breaker for an unnamed US hyperscaler aimed at Nvidia's Rubin Ultra generation. Prototypes are due at the end of the fourth quarter of 2026. The company raised $27.7m in May, holds $41.3m of cash and guides to burning about $10.4m this year.

Ultralife, the month's best performer at 28%, makes lithium batteries and military communications gear and carries a market value near $118m. Its June-quarter revenue fell 1.3% to $47.9m. Gross margin rose 590 basis points to 28.9%, but 230 of those points came from a one-off refund of tariffs collected under the International Emergency Economic Powers Act (IEEPA). The genuine news was order flow: backlog reached a record $117.5m, up 39%, and roughly $130m by early August on defense pull-through. At 2.65 times trailing gross profit, 0.89 times book and 8.3 times forward earnings, the market is plainly not paying for artificial-intelligence content here. It is a defense restocking story that happens to sit in the same neighborhood.

The suppliers that ship fell instead

Vicor, which makes the modular direct-current converters that step a rack bus down to the volt-level rails a processor draws, had the best quarter of its cycle. Stripping the prior year's $45m patent settlement, core revenue grew 49.3% to $143.4m. Gross margin expanded 280 basis points sequentially to 58.0%, far above the 52.6% it earned across 2025. One-year backlog rose 145% to $379.7m, and full-year guidance went above $600m. The shares fell 24.9% over three months. Price per dollar of trailing gross profit has compressed from about 43.8 times in May to 33.9 times — still nearly four times the 9.1 times of a year ago. Its litigation is live: the US International Trade Commission opened a new Section 337 investigation in February naming Monolithic Power Systems, the rival that took the H100 socket Vicor lost.

Bel Fuse, a maker of magnetics, alternating-to-direct-current power supplies and Cinch connectors, is the sharpest disconnect. Revenue growth accelerated to 25.2%, gross margin rose 120 basis points and operating income grew 47.4% — roughly twice the pace of sales. Data solutions revenue reached $58m, up 55%, on the start of a high-performance-computing ramp. Defense, at $66.5m, is still the bigger line. The stock fell 8.8% in the month after that beat-and-raise, leaving 26.0 times forward earnings against consensus for 45% earnings growth this year.

Navitas is the one name whose decline the numbers support. The gallium-nitride and silicon-carbide designer is one of ten silicon suppliers named in Nvidia's 800-volt reference architecture, and by far the smallest. June-quarter revenue was $10.5m, down 27.3%. Across four quarters it has produced minus $0.6m of gross profit on $36.5m of revenue. Diluted shares are up 18.6% year on year, including $373m raised at $21.89 — some 40% above where the stock now trades. Even after a 46.5% three-month fall it is held at 92.7 times trailing sales.

Why good quarters did not pay

The gating fact is timing. Full-scale 800-volt deployment arrives with Nvidia's Kyber racks in 2027; Navitas dates its sidecar racks to mid-2027. That is five or six quarters of waiting, and long-dated revenue is what a discount rate punishes. In late July the PHLX Semiconductor Index shed more than $1trn over three sessions as 30-year Treasury yields touched 19-year highs. Vicor and Navitas both slipped into downtrends by 20 August, their 50-day averages crossing below their 200-day, after trading in clear uptrends in May. Bel Fuse's uptrend weakened over the same weeks.

So the theme did not stall. It rotated — out of the companies reporting the revenue and into the two that have none to report.

The setup

Where it stands — Ultralife and Ideal Power carried the group's month while Vicor, Bel Fuse and Navitas fell despite two beat-and-raise quarters. Would confirm — Bel Fuse third-quarter sales landing at or above the $205-225m guided range with gross margin holding 39-41%. Would invalidate — Vicor's one-year backlog falling below $379.7m, or book-to-bill dropping under 1.0. Watch next — Ideal Power's hyperscaler circuit-breaker prototypes, due at the end of the fourth quarter of 2026. Valuation — Vicor is at 33.9x trailing gross profit and 26.6x forward, against 43.8x in May and 9.1x a year ago.