A square millimeter of leading-edge DRAM now carries more selling value than TSMC is assumed to charge for a square millimeter of 2nm logic wafer, according to a comparison by Kurnal Insights that Tom's Hardware reports and, to its credit, takes apart.
The arithmetic, as Tom's Hardware lays it out, starts with leaked wafer prices: $20,000 for a 300mm wafer on TSMC's N3, or about $0.283 per mm², and $30,000 for N2, about $0.424 per mm². Those are nominal figures, with no allowance for wafer edges, dicing, test structures or yield. On the memory side Kurnal takes $1.50 per gigabit and multiplies by bit density, which gives $0.329 per mm² for 1y-class DRAM at 0.219 Gb/mm², $0.410 for 1z at 0.273 Gb/mm², and $0.654 for 1b at 0.436 Gb/mm². By my arithmetic that puts 1b DRAM 54 percent above the nominal N2 number, and values the 70,686 mm² of a full 300mm wafer at roughly $46,000 of DRAM.
Here is the catch: the two columns measure different things. Tom's Hardware makes the distinction itself: the N2 and N3 figures are what TSMC is assumed to charge for processing a wafer, while the DRAM figures are the potential selling value of the bits on that area of silicon. One is a foundry's price, the other is a memory maker's revenue. Nobody is claiming that a DDR5 die costs more to fabricate than an N3 compute die; Tom's Hardware says plainly that it does not. What the comparison shows is that a memory company now collects foundry-grade revenue per square millimeter on silicon it fabricates itself, which is a statement about margin, not cost.
Spot prices back the input. Tom's Hardware cites DRAMeXchange putting 16Gb DDR5 eTT chips at a session-average $24.80 on September 21, or $1.55 per gigabit, which lifts the 1b figure to about $0.676 per mm², 3 percent above Kurnal's estimate. Spot is the wrong market to anchor on, though, and TrendForce's own update of September 16 says why: "In the spot market, quote inquiries for DDR5 chips from major suppliers slowed this week, and prices for certain chips have begun to show signs of softening." Decoded, the comparison was run on a thin, sporadically traded price at what may turn out to be its peak. Micron, Samsung and SK hynix sell the bulk of their output on contract, and Tom's Hardware notes those prices are unknown and may not be as high.
Two more caveats cut in opposite directions. Packaging is left out, and logic packaging costs more, which flatters the DRAM column. TSMC's actual wafer price depends on the customer and the volume, so the $30,000 N2 figure could be high or low for any given buyer. Tom's Hardware ends where the evidence does: "To that end, we cannot state for sure that DRAM makers get more money for their wafers than TSMC does for its logic wafers."
What survives the caveats is still worth having. Tom's Hardware says memory makers are getting considerably more money for their silicon than they did historically, and a per-area value within striking distance of a 2nm wafer price is a concrete way to measure that. It also marks the exposure: a foundry's price per wafer is set by contract and process cost, while the DRAM value per mm² is set by a shortage. If supply catches up, the right-hand column moves first.
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