Legit Reviews

Problem: Transfer rates between hard drives are extremely poor!

First off, the motherboard is an nForce 4 AMD Edition SLI 16x Asus A8N32-SLI Deluxe. The hard drives are Western Digital 2500KS (16MB cache, SATA300MB/sec) and a single Western Digital 7500AAKS (16MB cache, 300MB/sec).

The problem is transfer rates between the 750GB drive and the dual 250GB drives. With the OS (Vista Ultimate x64) idle, a transfer from the 750GB to one of the 250GB (not in RAID anymore, using the big 750GB to un-RAID the 250GB drives without losing data or burning huge numbers of discs) reads transfers at 20MB/sec, no more. In RAID0, the transfer rates from the 500GB RAID0 topped at 50MB/sec to the 750GB drive.

Naturally, with 300GB+ of data to move this is frustrating as it makes the whole backup/restore process take an obscene amount of time. It took 2 hours just to dump the RAID0 array to the 750GB drive! Average was about 45MB/sec (maximum 79MB/sec, minimum 20MB/sec).

I have tried re-installing the latest nVidia chipset drivers to no avail. Horrible transfer speeds are making this un-RAID a nightmare! Help!

Before typing I will remind you of my stupidity.

Now, that said....shouldnt the transfer rates from 1 drive be half what the raid array was anyway since you cant read from both drives at once?

Mike

1 other thing, and it sounds even more stupid ( stupider ) - try removing both the 250gb drives after transferring everything to the 750, then restart, then shut down and install 1 drive, restart, then shut down and install the other, then restart again. Ignore sata being hot swappable etc.

Sounds like a pain in the arse, but I had a slow 120gb drive until I did this exact same thing - just reinstalled each drive other than the boot drive one by one, and then it worked - well formatting each one in between using FULL format not quick also.

stupid out.

Yes the transfers are half what the RAID array were, but since the RAID array could barely top 40MB/sec, something was very wrong anyway

I'll try swapping out drives then, thanks, I would have not thought of that.

The RAID array was not compressed. Do compressed files inhibit performance this much? I formatted the volumes as NTFS Compressed but am uncompressing them now.

Writing to a RAID 0 array is slower than reading and never works out a double the performance of a single drive. This is because on-board controllers are software based.

~40mb/sec does sound slow though, you should be in the high 50's or mid 60's.

Have you installed the latest motherboard bios and OS drivers?

Def sounds like a bios / OS device manager issue. Of course if you had a handy alternate system to benchmark the drives on it would illiminate the raid being the issue.