One artificial intelligence (AI) stock is turning demand into billions of dollars. The other has fallen almost 59% from its high just as its first serious production ramp is supposed to begin. Investors waiting for the winner to become obvious may discover that the share price got there first. But first, why look at AI at all?

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Think small
I get it, every one and their mother have already looked at AI stocks. Been there, done that. Yet data centres are different. AI data centres don’t run on processors alone. Thousands of chips must constantly exchange enormous amounts of information. As clusters grow, older copper connections struggle with speed, distance, heat, and power use. Faster switches and optical links become the nervous system connecting all that expensive computing muscle.
This creates two ways to invest. An established manufacturer can earn from today’s equipment orders, while a smaller photonics developer could win if its technology becomes tomorrow’s standard.
The timing makes this comparison urgent. One company just raised its outlook and expects growth to accelerate in 2027. The other says volume shipments should begin during the second half of 2026. Those milestones could widen the gap quickly, so which stock deserves fresh money now?
Celestica: Already proven
Celestica (TSX:CLS) designs and manufactures hardware used in AI data centres, communications networks, aerospace, defence, and industrial systems. Its high-speed switches and custom computing platforms help hyperscalers build larger clusters, giving investors exposure to AI infrastructure without guessing which chatbot writes the best apology email.
Second-quarter revenue surged 62% to US$4.7 billion, while adjusted earnings per share (EPS) climbed 83% to US$2.54. Management raised its 2026 outlook to US$20.5 billion in revenue and US$11.30 in adjusted EPS. It now expects revenue growth to accelerate beyond 65% in 2027, with earnings growing even faster.
At roughly $441.50 at writing, Celestica trades near 36 times earnings. That isn’t cheap, yet it looks reasonable beside 87% forecast earnings growth. Customer concentration, component shortages, or slower hyper scaler spending could still punish the shares, which is why I would build the position gradually among other Canadian growth stocks.
POET: on the approach
POET Technologies (TSXV:PTK), meanwhile, develops optical engines, light sources, and modules that move data using light. Its Optical Interposer integrates electronic and photonic components at wafer scale, potentially making fast connections smaller, cheaper, and easier to manufacture.
The promise is moving toward a commercial test. POET stock expects volume shipments to begin during the second half of 2026 and wants capacity to exceed one million units monthly by the end of 2027. More than 10 active customer engagements could eventually produce over US$100 million in annual revenue, while a Lumilens agreement includes an initial US$50 million order tied to development and qualification milestones.
The current numbers haven’t caught up, though. First-quarter revenue was only US$503,389, against a US$12.3 million net loss. At US$8.61, POET stock carries a market value near US$1.5 billion despite trading almost 59% below its US$20.81 high. Its US$830-million-plus cash position reduces funding pressure, although raising that money diluted shareholders substantially.
Execution remains the real risk. POET stock must qualify products, manufacture them reliably, and convert forecasts into repeat orders. April’s cancellation of its Celestial AI orders shows how quickly anticipated revenue can disappear. A delayed ramp could leave investors paying handsomely for excellent laboratory results.
The better buy right now
Celestica is my winner. Its valuation is demanding, but earnings, free cash flow, raised guidance, and new programs support it. I would start with part of a desired position now and add on pullbacks rather than waiting for a perfect entry that AI demand may not provide.
That said, POET stock could deliver the larger percentage gain if shipments arrive on schedule, making it a fascinating speculative position for investors comfortable choosing growth stocks. I would keep it small until production appears in revenue. Celestica sells the working toll road, POET stock may own a faster on-ramp. Right now, I would rather collect traffic than bet the interchange opens on time.