This RAM works on both the ASUS A7V and MSI Pro2A mobos. I've bought these 64x4 chips from them before. Unfortunately, the last three DIMMs that I ordered from them, I had to RMA them back because they didn't work on these two boards. UPS shows that they received it on April 4th. I called UpGrPl on the 9th and they confirmed that these DIMMs were defective and told me that they were semding out replacements, probably that day. Today (16th), I called and they said that they will ship out today and that I will receive a UPS shipment notification (like I usually do). The CSR said that they usually try to turn around an RMA request within 5 working days. If they ship them out today, turnaround time would have been 8 days. That's a little slow. You'd figure that they would try to get it out to you as fast as possible since they sent you defective merchandise. Guess that I'll have to wait and see.