Design and Features
The ThinkCentre M91p's exterior matches that of the previous Lenovo ThinkCentre M90p USFF , from its no-nonsense enterprise chassis to its tray-loading DVD drive. Like the M90p, the M91p is easy to open, easy to service, and easy to deploy. These traits, common among enterprise class PCs, are evident in the M91p's Kensington lock port, blue-colored grab handles for the serviceable parts, quick-swap hard drive, Intel vPro certification, and ThinkVantage utilities to help the IT manager handle company desktops. The system has eight USB 2.0 ports; faster USB 3.0 or eSATA ports are not present. Access ports are limited to the front and back surfaces of the system, which makes it easier to mount under a desk on in a cubby hole. The system uses an external AC adapter, which is less convenient than a standard three-prong cord, but AC adapters are pretty common for USFF systems. There's a DisplayPort jack on the back, for new business-class monitors, and a VGA port for old-school displays.
Performance
The basic improvement in the M91p over the M90p is the inclusion of a new Sandy Bridge Intel Core i5-2500S processor in place of the older Clarkdale i5-660. The i5-2500S has the latest-generation built-in Intel HD Graphics 2000, and along with the system's 4GB of memory, gives the M91p the legs it needs to last your company more than a few years. The M91p took a spritely 1 minute 21 seconds to complete our Handbrake video conversion test and 3:12 to finish our 12-step Photoshop CS5 test. For comparison, the Core i7-2600 - powered Dell Optiplex 990 is a bit quicker (1:11 in Handbrake, 2:57 in CS5) thanks to its more powerful quad-core processor, though of course it's quite a bit more expensive. Closer in price and performance is the HP 8200 Elite USDT (9 direct, 4 stars), which uses the same Core i5-2500S as the M91p, and achieves similar results (1:21 in Handbrake, 3:16 in CS5). Likewise, the M91p's PCMark 7 score of 2,558 is one of the better ones we've seen on a business PC, handily beating the HP (2,190) and in striking distance of the Dell (2,601). This means that the M91p is fast enough to last the four to five years you'd expect from a new business PC.