Lenovo ThinkPad R50 1831 compatible 1GB 333MHz DDR SO-DIMM Black Diamond memory. Compatible computer model: Lenovo ThinkPad T42 2374, T41p 2379, G41 2881, R51 2894, X40 2386, R51 2883, T42 2375, T42 2376, R50 1830, R51 1830, X31 2884, R51 1841, X31 2672, X31 2885, G41 2886, X32 2885, T42 2378, X31 2673, T42 2373, R51 2895, R50 1836, G41 2882, T42p 2376, T42p 2379, G41 2388, T42p 2374, R51 1831, T41 2379, R51 2889, T41p 2378, R50e 1860, R50e 1846, G40 2388, R50e 1848, T42 2379, T42p 2378, X40 2371, X40 2372, T41 2378, X40 2382, R50e 1834, R50 1841, R51 2887, R50 1831, R50e 1843, R50e 1847, R50 1840, T42p 2373, R51 1836, T41 2374, R51 2888, R50p 1832, R50e 1859, R50p 1833, R50e 1844, R50e 1842, X32 2673, R50e 1849, X32 2884, X32 2672, R51 1840, R51 1829, R50 1829, T41p 2374, T41 2376, T41p 2373, T42, T41 2373. Black Diamond Memory offers the most extensive line of memory solutions today. With our decades of experience specializing in memory, Black Diamond Memory is a proven manufacturer to the semiconductor industry. Our great products combined with our world class service and support have helped us to where we are today. When you have an Black Diamond memory chip, you can count on it being the best available memory for your system. Our system specific Branded Memory line delivers in performance, and is designed to be guaranteed in compatibility with your system. Each of our memory chips come with a lifetime warranty for your peace of mind. Use our Upgrade Configurator to easily find the correct memory module for your system. Please keep in mind that this memory will ONLY work on the models listed above. 15% Restocking fee will apply for non-defective items.