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I recently upgraded my Windows XP (!) computer to a single Crucial M4 SSD. The system is running very fast and without problem, but running HD Tune Pro (and CrystalDisk) revealed that sequential read rate is only 80MB/s (with a block size of 64K) and write is 60MB/s. Also, IOPS is only 6,000 (for 4KB). This too seems very low.

There are two SATA controllers (why?) on the motherboard: Promise and VIA. The spec ( ) suggests that the Promise controller (which I am currently using) could be limited to SATA 1.5. However, if that were the case then the transfer rate should be much higher, I think. 1.5 Gb/s = 187.5 MB/s. Also, why is the IOPS so low? (6,000 * 4KB = 24MB).

Research on the internet suggests the performance should be over 400MB/s, so the drive should be much faster.

Currently using the Promise SATA port. I tried plugging the SSD into the VIA SATA port on the motherboard, but I get a bios error "No BIOS is installed." and it will not boot. It's strange because when there is no hard drive installed I get "No hard drives found."

I installed the Promise 378 drivers during the Windows install.

Do you think there is a problem with Windows XP, or perhaps the drivers? Could the motherboard be set up for RAID? I tried changing the settings, but it didn't help.

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migrated from Feb 11 '12 at 14:03

This question came from our site for system and network administrators.

Something wrong with XP?? You dare say a 12 year old OS isn't perfect!? – surfasb Feb 11 '12 at 17:05
Actually XP is awesome! I just didn't know if there could be issues since SSD's are new. – B Seven Feb 11 '12 at 17:38

How did you perform the upgrade and the copy process from your old HDD to the SSD?

If you don't use a tool that is aware of the SSD special properties like the requirement for correct partition alignment you will loose a lot of speed.

Additionally you should always use your southbridge SATA ports for SSDs. As long as you don't own a special PCI-E 4x controller card the southbridge will be faster. Using this port you can get up to 200-300MB/sec; the maximum speed is not possible because it is only a SATA-3Gbit port.

And make sure the southbridge SATA port is set to AHCI not IDE.

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Are both Promise and VIA SATA ports on the motherboard southbridge? – B Seven Feb 11 '12 at 17:40
I did not successfully "migrate" the old system files, so I used the Windows XP installer to format the drive, and went through the long (but fast) installation processs. Can I reformat the drive without going through the whole installation process again? What is the proper way to format the drive so that it has correct partition alignment? – B Seven Feb 11 '12 at 17:43
Your system has a VIA southbridge chipset, the Promise is an extra chip. – Robert Feb 12 '12 at 13:42
I tried to hook it up to the VIA SATA port, but the BIOS complains "No BIOS is installed". I think it is because that SATA port does not work with SATA 6Gb/s, and you must force 3Gb/s with jumpers on a HDD to get it to work. There are no jumpers on the SSD, so maybe there is a way to do it through software... – B Seven Feb 13 '12 at 0:10

Please update to the latest firmware and check again.

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Windows XP and SSD doesn't go hand in hand, because XP predates trivial SSD feature called TRIM.

Does Windows XP support the SSD trim command?

What I would suggest you to do right now is:

Read This:

Browser a little bit of

Google "SSD tweaks"

Revert the state of SSD back to the factory condition, that's something like filling it with zeros. I bet Crucial have a software tool for that, I know that OCZ does have one.

Install OS that natively supports TRIM, for example WIN 7 HP

Never try HD Tune or any other performance tests that are done just to get the numbers. Try launching some game or something. SSD memory cells have a finite amount of times they can be written to and using them for tests isn't a really good idea.

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