DON'T THROW AWAY YOUR DDR4-2666
$110 for a 16GB DDR4-2666 kit on eBay. Generic brand. OEM pull. No warranty.
Two miles away on Facebook Marketplace: same spec, name brand Corsair, $55. Same county, $40. A single 8GB stick for $10.
Someone is paying eBay prices. Don't be that person.
The Market Is Broken In Your Favour
DDR5 was supposed to kill DDR4. It didn't. DDR5 is still $80–120 for 16GB so nobody upgraded, DDR4 production contracted, and prices went up. The dumb outcome. We're living it.
Meanwhile on FBMP, San Diego County, this week:
| Listing | Capacity | Speed | Price | $/GB |
|---|---|---|---|---|
| OLOy single stick, San Diego | 8GB | DDR4-2666 | $10 | $1.25 |
| TForce Vulcan 2x8, Carlsbad | 16GB | DDR4-2666 | $40 | $2.50 |
| Corsair Vengeance LPX CL15, Escondido | 16GB | DDR4-2666 | $55 | $3.44 |
| TeamGroup T-Force Vulcan 2x8, Cardiff | 16GB | DDR4-2666 | $110 | $6.88 |
Same spec. Same county. $40 vs $110.
Some sellers are counting on you not knowing that. Don't give them the satisfaction.
eBay wants $95–110 for the same sticks. The local floor is $40. That gap is yours.
2666 Is Fine. Stop.
DDR4-2666 runs at spec on every LGA1700 board. The i5-12400F doesn't care. Ollama doesn't care. Rust at 1080p doesn't care. The benchmarks showing a gap between 2666 and 3200 are synthetic bandwidth tests nobody runs in real life.
If it's in a drawer, put it in a machine.
The Free Option
Corporate IT refresh is happening right now. Offices that bought DDR4 machines in 2019 are clearing them out. That memory goes to asset disposal firms, surplus auctions, and — constantly, infuriatingly — the bin.
- Freegle/Freecycle/FBMP: businesses post "free old desktops." They want it gone. You want the RAM. 30 seconds with a screwdriver.
- E-waste drop-off events: show up. Bring a screwdriver.
- eBay "ddr4 lot untested": $30–50 for 10–20 mixed sticks. Test with MemTest86. Even 50% yield is $5/stick.
- Government surplus auctions: $15 workstation. Has RAM in it. Do the math.
One thing: run MemTest86 on anything pulled. Two passes, zero errors. Takes one night. Not optional.
Watch For The Laptop Trap
SO-DIMM is not DIMM. Laptop DDR4 physically cannot go in a desktop motherboard. Listings don't always say "laptop" in the title — check the photo. If the stick is about half the length of a standard DIMM, it's SO-DIMM. Pass it.
Short Version
The local floor for 16GB DDR4-2666 is $40. eBay wants $110 for the same thing. The working sticks are out there in surplus lots, office clearances, and FBMP listings from people who just want them gone.
Look locally first. Always.
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