(This is a repost from Anandtech forums since I thought posting in an actual Disk Storage Systems forum might get more of a response. I also apologize for the length of the post, but I tried to include as much info as I could.) Hi all! I'm having a problem with my RAID setup and I need some advice. Here are the specs: Windows Server 2003 Standard AMD Athlon 2100 Soyo SYK7V Dragon Plus MB 512MB Kingston Value RAM (I think) 10GB WD HD That's the base system. Here's the storage system: Syba PCI hardware RAID controller card (based on the SIL0680 2-port PATA card) Two Seagate 7200RPM 300GB PATA drives (matched set) PCI USB\Firewire card (to back up RAID array to external USB drive) The storage system is set up in a RAID 1 config. Drives have passed SMART tests and SeaTools tests. All drivers are newest ones available. Now the problem. I was making a backup of my main system the other day and the backup failed by saying the image was corrupted. I started troubleshooting and found that I could read files from the RAID array with no issues but when writing a large file to it it would corrupt the file (this was checked via MD5 hashes). I could not format the array in Windows (received an error) but I was able to format the drives after breaking the array and formatting them separately. I recreated the array and readded the drives, and during this process I found that when the Secondary Master was offline I coulc write to the array with no corruption issues. I tested and confirmed this and at that point thought it was a bad drive. I then re-built the array with the Primary Master and the corruption was present. Wanting to be sure, I then removed the Secondary Master and tried the write test and found that I the corruption was not present there! I then re-added the Secondary Master and the corruption re-appeared. I then broke the array and formatted and tested to each individual drive with no corruption. I then put the array back together and was able to copy files without the corruption, so I thought I might have fixed the problem. I then copied some folders with a large amount of data over to the array but when I checked the files I fould they were corrupted. My question is this: Can the RAID card go bad and cause this kind of corruption? Meaning that if the card only writes to one disk in the array there is no corruption but if both disks are in the array the data is corrupted? Any help\suggestions anyone may have would be greatly appreciated!