It's not 100% sure why NVIDIA needs these engineers but there are some rumours that the firm is hiring folks to work on a new PlayStation (4?) GPU.
NVIDIA does not have any products that integrate eDRAM now, however, Beyond3D forum members believe the job posting is for an upcoming GPU for Sony’s PSP successor. This makes sense as the Sony PS2 and PSP GPU feature eDRAM. Although NVIDIA is a likely candidate as the GPU designer for Sony’s PSP successor, neither companies have made any announcements.
Other gaming consoles that take advantage of eDRAM include Nintendo’s Gamecube, Wii and Microsoft’s Xbox 360; however, all three consoles feature AMD ATI designed graphics processors. On the eDRAM side of things, IBM recently unveiled the fastest eDRAM technology yet