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IBM ThinkPad X61s 7666-xxx Memory Upgrades | Seifelden

Your system

IBM ThinkPad X61s 7666-xxxMemory Upgrades

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6 guaranteed-fit options

This option is out of stock.

Free tools from Seifelden — no purchase needed.

Seifelden Upgrade AssistantFree

Checks the drivers on your IBM ThinkPad X61s 7666-xxx, installs the safe updates Windows offers, guides the rest to the official download — and confirms exactly which of the upgrades above your machine has room for.

Guaranteed-fit promise

Every kit is matched to your machine's slots and checked against its published specs before we list it.

System at a glance

Memory type: DDR2
Slots: 2
Max memory: 4 GB

View full system details

System specifications for IBM ThinkPad X61s 7666-xxx

Specifications reported for the IBM ThinkPad X61s 7666-xxx.

Memory type: DDR2
Form factor: SODIMM
Memory slots: 2
Maximum memory: 4GB
Max per slot: 2GB
Rated speed: 667 MT/s
Processor: Intel Core 2 Duo

Good to know

Faster modules automatically run at your system's maximum supported speed.
Maximum capacity per slot is inferred from total capacity ÷ number of slots.

Compatibility is based on published specifications, not yet confirmed against a manufacturer tool.

Details & what it sends

Every upgrade for the IBM ThinkPad X61s 7666-xxx is out of stock right now

We've already verified which memory and storage upgrades fit this exact machine — they're just not in stock at the moment. Leave your email and we'll tell you the moment any of them is available again. Guaranteed fit, no wrong parts.