SCSI slower than IDE drive

I have an Adaptec SCSI 29160N Adapter card running a 10,000rpm IBM 18GB HDD, a CD-ROM, and a CD burner. The HDD is mainly used for processing video data. The OS is Windows 2000 Pro Ver 5.00.2195 Service Pack 3, and the initial Paging Size File for each HDD is set at 1.5x the RAM.

In addition, there are two IDE drives, with the Win 2000 Pro OS installed on one of these. All drives use FAT32 file systems.

I had a EPOX 8kHA+ motherboard, and the Dacris benchmarking program shows the IDE drive transfer rate is 26.0MB/sec, and the SCSI HDD transfer rate at 75.5 MB/sec, which is only to be expected. These transfer rates are real-time, based on reading 1MB of data from any nominated drive, and measuring the time to do so.

This EPOX motherboard received terminal injuries when after flashing the BIOS, I forgot to remove the power cable for the back of the PC before discharging the CMOS (duh!)

I have since installed the latest EPOX 8K9A2+ with 256MB of DDR PC2100 RAM, and a new SCSI 10,000rpm SCSI drive, but still running the same Athlon 1600+ processor.

I have also downloaded and installed the latest Adaptec SCSI drivers(6.1.530.201), the APSI drivers (v4.71), the latest VIA motherboard drivers (4in 1 chipset V4.43), and the latest nVidia AGP card drivers (Detonator v.41.09).

I have re-run the Dacris benchmarking program, and found the IDE drive still measures 26MB/sec, but the SCSI data transfer rate is now only 19MB/sec, repeated over a number of days.

This is confirmed in Sisoft Sandra 2003 File System Benchmark, where the IDE drive data rate is 24.6 MB/sec, and the SCSI drive data rate is 25.5 MB/sec, and by PCMark2002, where the IDE drive scored 854, and the SCSI drive scored only 530, whereas in fact I was expecting a score 2-3 times that of the IDE drive.

Can you please advise how this poor SCSI transfer rate might occur, and what I need to do to fix it?
1 answer Last reply
More about scsi slower drive
  1. Quote:
    I had a EPOX 8kHA+ motherboard, and the Dacris benchmarking program shows the IDE drive transfer rate is 26.0MB/sec, and the SCSI HDD transfer rate at 75.5 MB/sec, which is only to be expected. These transfer rates are real-time, based on reading 1MB of data from any nominated drive, and measuring the time to do so.

    Well for starters no IBM 10k drive is capable of delivering a 75.5 MB/s transfer. This is a fact, only perhaps from its buffer can such a high rate of transfer be possible. I am not familiar with the benchmark program you use I suggest trying winbench 99 disk inspection test for raw transfer speed. It would be of more help if you posted the drive(s) model numbers so I could look up what type of performance you should expect.

    First you need to confirm that your SCSI card is working in U160 mode, this should be seen on the scsi cards post screen. If not enter its bios and make sure it is configured correctly.

    Secondly you have introduced two variables, a new motherboard and a new hard drive. When trouble shooting, it is always advisable to only introduce one variable into the equation at a time. I suggest going back to your original hard drive and testing that. If your transfer rate goes up it is most likely a jumper issue on the new hard drive. Are both drives 68 pin or is the newer one an 80 pin drive with an adapter? If so then it may be the adapter that is the issue.


    It's not what they tell you, its what they don't tell you!
Ask a new question

Read More

Hard Drives SCSI Storage