1.This extra slim (XS-D) v2.5 board provides 128MB of SDR SDRAM memory for cores requiring alarge (Greater than 512KB) of memory including the core for Neo Geo. Although the DE10-Nano has built in DDR3 R AM, it has a high latency and is not suitable for the timings required of retro device for edO DRAM.2.So if a core requires precise memory timings, then the onboard DDR3 cannot be used. Every one of my boards uses the high quality alliance memory paired.3.You can be confident knowing each 128MB SDRAM extra slim (XS-D) v2.5 board has been tested for over an hour at 140 MHz. I have also tested each with the console core for Neo Geo, for Acorn Archimedes (Archie) core, for Game Boy Advance core, for sega core and in for Neo Geo games which require a 128MB module to play this ensures no issues are present.1.Suitable for Terasic DE10-Nano FPGA Board2.128MB SDRAM Capacity3.100% for the Neo Geo ROM Library Playable4.Alliance Memory AS4C32M16SB-7TIN Chips5.For MiSTer IO Board Compatible6.Fully assembled and testedMaterial: plasticcolour: bluePackage Contents:1 x Real Time Clock BoardOnly the above package content, other products are not included.Note: Light shooting and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.