The S900 series of machine from Mac clone manufacture UMAX represented the company's high-end offerings. Based on the same motherboard that is found in Apple's 9500 machines, the S900s came in 150, 180, 200, 225, 233 and 250Mhz models. Some of these models were relatively short lived as UMAX quickly moved on to a faster version of the machine as faster processors became available. These machines came in a Tower form factor and were considered the high-end price/performance bargains compared to computers in their product category coming from Apple and other clone manufacturers (most notably Power Computing). Though lower in price UMAX cut some corners in the performance area that made the speed of these machines somewhat slower than their competitors models running at the same clock rate.

Though there was some variation in features (for specific feature of each machine see sidebar "Facts At A Glance") most of the models came with the following:

Six PCI slots, one of which was occupied by an IMS TwinTurbo 128M graphics card (with either 4 or 8MB of VRAM), and one of which was modified to take a UMAX manufactured dual Ultra Wide SCSI and Fast Ethernet card.

The SCSI/ethernet card was an optional add-on for all machines except the S900/250 where it came preinstalled.Its PCI slot can also take standard PCI cards. The processor of the S900s resides on a removable card making upgrades simple. The installed L2 cache is 512K which is soldered to the motherboard and thus not upgradable. This low amount of cache hobbles the higher clocked machines and was in large part the reason they had trouble keeping up with their competition in the speed department. They came with high-speed drives ranging from 2.1GB to 4.0GB and have 4 free drive bays. The Tsunami motherboard was modified in several ways by UMAX. First it has a second slot for an additional processor. This was to allow multiprocessing without the necessity to discard the original processor. The S900s also have a specific PCI to PCI bridging chip that allows for faster processing of data passing between two PCI cards when they are installed in adjacent card banks. The motherboard has 8 DIMM slots allowing for up to 1GB of RAM, and memory in these machines is capable of interleaving which will give a marginal improvement in processor performance. One complaint about these machines is that some users found them rather noisy during operation..

Below you will find the MacBench 4.0 results for most of the processor upgrades available for this machine. These results are what the individual manufactures publish for their cards. In other words the speed trials were run by the manufacturer. For an independent evaluation of these cards check the Processor Upgrade Page to see if we have results available. The bar graphs below express results as a percentage of improvement over the base machine, which receives a score of 100%. Further down the page you will find a table with the actual MacBench scores.