These High-Performance CAS 4 Low-Latency modules are designed and built for the true Power User seeking every last drop of system performance. Compared to standard spec CAS 5 modules, this CAS 4 SPD Optimized 4.0GB Kit provides roughly 5-6% more memory read/write maximum bandwidth. Real-world application benefit varies, but typically is at best a 1-2% benefit compared to having 4.0GB of standard spec CAS 5.0 memory.

Barefeats has done testing online here which you can see our OWC CAS4, CAS5 and competitor’s modules compared.

Whether you select our CAS 4 or our CAS 5 4.0GB Kit, just by upgrading your Intel Core 2 Duo Mac to 4.0GB gives a huge boost compared to a stock config with only 1.0GB or even 2.0GB installed. Amazingly even when you’re going from a 2.0GB to a 4.0GB with our standard CAS 5 memory can literally make your Mac 3X faster with certain real-world application usages. Only have 1GB and going to 4.0GB? – Prepare to be blown away! No matter which OWC memory you install, the most significant performance benefit comes from that additional memory being there. Our real-world memory performance test series which compares Apple factory installed base memory configurations vs. the same Intel Macs with up to 4.0GB of our standard Apple Spec CAS 5 memory by clicking here.

OWC offers rebates on memory!

A rebate from OWC on your old memory module helps make upgrading to higher capacity chips even easier! From the date of purchase of a qualifying new memory module from OWC, we allow 60 days for you to return your old memory for a cash rebate! Once you've received and are satisfied with your new memory, just fill out our online rebate form or contact OWC Customer Service by phone Monday - Friday between 8:30AM and 8PM for a rebate RMA.

Please allow up to 14 Days from the time we receive your memory for testing and rebate processing. Your memory must be functioning correctly to qualify. Upon successful testing, a rebate check for the qualifying amount will be mailed to the billing address used on your new memory module purchase. It's that easy! :)

When you upgrade your memory from Other World Computing, a rebate for up to the same number of memory modules purchased is available for the return of your old module or modules! Module(s) must be in working order.