I recently purchased a 250GB MAXTOR DIAMONDMAX 10 Ultra16 UltraDMA ATA/133 hard drive for my Dell Dimension 4100. I knew prior that my motherboard supported up to ATA/100 but I read that there was no compatibility issues with this. I installed the drive, formatted with NTFS and split the drive into two 125GB partitions. The drive worked perfectly until I tried copying large (500MB+) files from my 40GB drive to the new 250GB drive. Every time it would stop part way and give a write error message then the drive letters would disappear until the system was rebooted. I decided to buy a PCI controller card that fully supported UltraDMA ATA/133 so that I could use the drive to its full potential. The chipset on my new PCI to IDE card is Silicon Image Sil0680. I hooked up the drive to the PCI card, installed the latest drivers and still have the same issues. Are there any ways around this?