Drives

HP recommends Windows Vista® Business

How does this memory bandwidth impact the HP xw4550 system performance?

Many technical applications require huge amounts of memory bandwidth, especially those that use 3D graphics or that have a large percentage of floating point calculations. These applications will benefit from the massive memory bandwidth provided by the HP xw4550. Additionally, no configurations using three memory modules are supported.

Memory latency is another very important factor. At the highest level, latency is a measure of how long it takes the memory subsystem to respond to a cache miss in the processor. The lower (shorter) the memory latency, the better the application performance, especially for applications that “thrash the cache.”

Does the memory for the HP xw4550 have to be ordered in pairs? What is the maximum memory configuration?

To utilize the dual-channel memory architecture advantages, memory must be installed in pairs. However, a single DIMM will work in the system (i.e. you could put 1x256 MB in the system). It is highly recommended that memory be added in pairs, as the performance benefit is substantial. Because of this, no single DIMM configurations are offered on xw4550.

When installing memory in the HP xw4550, pairs must be matched in size and speed (i.e. 2x512 MB/667 MHz, not 1x512 MB/667, 1x1 GB/667) and multiple pairs must be matched in speed. The HP xw4550 has 4 DIMM slots (2 dual- channels) and supports up to 4 GB of physical memory.

Does the HP xw4550 offer ECC and non-ECC memory? If so, what speeds are/will be offered?

The HP xw4550 offers both ECC and non-ECC memory. The following table outlines what memory is available:

DIMM size/speed	256 MB	512 MB	1 GB
DDR2 667 MHz, ECC	Not Available	Available	Available

DDR2 667 MHz, non-ECC

Available

Not available

What is ECC memory?

Why is ECC memory important?

“ECC” stands for Error Correcting Code or Error Checking and Correction. ECC memory modules have an extra chip that performs a comparison of the data that is read in and written out. This chip has the capability of detecting single and multiple bit errors and correcting single bit errors on the fly. If this extra chip detects a single bit error, it will correct the discrepancy and the system will continue to function without any interruption. If a multiple-bit error (which is extremely uncommon) is detected, the memory module will issue a non-maskable interrupt (NMI) which will shutdown the system, avoiding any data corruption in the system. Single- and multiple-bit data errors can go undetected without ECC memory.

Data integrity is always important, but when you are designing an airplane or automobile part, under a tight deadline on your TV commercial production, analyzing population densities for domestic policy reform, or managing your clients’ financial portfolios of millions of dollars, data integrity is absolutely vital. And in today's cut-throat competitive environment, work flow efficiency and utilization rates are also crucial. All HP workstations, including the HP xw4550, offer ECC memory which provides an extra level of data integrity, reliability, and greater system uptime.

Is the floppy drive really optional on the HP xw4550?

Yes. For ultimate price flexibility and/or security concerns, we now offer systems with or without the floppy drive. With the advancement of technologies like USB Disk Keys, bootable CD-ROMs/CD-RWs, external storage, etc. the necessity of a floppy drive has really declined over the past few years and many customers simply don't need them anymore. We offer the flexibility should you decide it is not needed on your HP xw4550.

Is the optical drive really optional on the HP xw4550?

Yes. Once again, for the ultimate in price flexibility and because of security concerns, we now offer systems with or without an optical drive. Microsoft has lifted a requirement that forced the integration of an optical device on previous systems, so this is now possible for the first time on the HP xw4550.

Does HP offer any other removable storage options?

Yes. HP offers an optional 16-in-1 Media Card reader that can be factory-installed on the HP xw4550. This device will enable users to quickly and easily transfer data between their workstation and their flash media (Compact Flash, Smart Media, etc). This device will occupy the bottom optical bay in the HP xw4550.