1GB RAM Memory Upgrade for the Dell OptiPlex 740 Desktop, Mini Tower and Small Form Factor Systems (DDR2-667, PC2-5300) Guaranteed Compatible with the Dell OptiPlex 740 Systems Speed up your system with up to 4.0GB of RAM! Lifetime Replacement Warranty! Will ship the same day when ordered at or before 4pm EST! All others ship next day! Fully-staffed call center to help with installation or inquiries! Call 866-335-1355 with questions or for help!