Note that your card may support even higher speed but your card reader may be limited by the OEM.Īlways test your card under Windows or Linux to get an estimate on the threshold. I tested my RTS525A with a SDXC card and got about 75MB/s read speed and 60MB/s write speed. This driver supports SDSC/HC/XC cards and UHS-I SDR12/25/50/104 and DDR50 modes. This driver is based on the Linux driver module `rtsx_pci/usb` which is contributed by engineers from Realtek and therefore is more mature than the FreeBSD/OpenBSD driver.īut I wrote this driver from scratch instead of blindly copying the code from Linux to macOS, so there is no compatibility layer (and performance degradation introduced by the compatibility layer) at all. Please use this thread for general discussion and test reports. I made a new driver for Realtek card readers, and I would like to invite people to join the beta testing.