Sudden drops in write/read speeds

[styles2018]

Hey, guys. I hope this is the right forum category to ask the question because I don't know what's causing the problem.

Anyway, over the last month or so, I've noticed while copying from one HDD to another HDD, or copying from HDD to external HDD or USB, write speeds randomly drop down by half until I restart the PC and then it's fine again.
So, for example, copying from one HDD to another, speeds are over 100 MB/s, but then when this drop happens they fluctuate between 55 MB/s to 70 MB/s. It's the same thing copying to external USB 3.0 Hard Drive. Also, when copying to my Sandisk Ultra Fit USB, before this happens, speeds are around 40 MB/s, but then they drop to around 15 MB/s.

Also, even after this speed drop happens, when I check speeds using CrystalDiskMark, they are still good. Here are some screenshots I took after the speed drop:

HDD #1: https://i.imgur.com/TQUcEx9.jpg
HDD #2: https://i.imgur.com/c9WzorF.jpg
External HDD: https://i.imgur.com/ywJpNPR.jpg
USB: https://i.imgur.com/ivmtBwc.jpg

I've also noticed two other small things when the speed drop happens. One is that when saving Word documents, saving takes just one second longer. It's barely noticeable, but it really is a second longer. The other thing I notice after the speed drop is when I open an image in IrfanView and then I want to overwrite it, it also takes a second longer for the window to show asking me if I want to overwrite an image. Before the speed drop, that window immediately pops up.

Other than this speed problem, the system works just fine. Even if I leave the computer on for a couple of days, the overall performance doesn't worsen; playing media files, surfing the Internet, watching videos online is just fine. There are no lags or anything else, I haven't had any BSODs or system freezes.


My specs are as follows:

Windows 7 Ultimate 64-bit
Motherboard: Asus M5A78L-M LX
CPU: AMD Athlon II X3 450
RAM: 2x 2GB Samsung DDR3-1333
GPU: NVIDIA GeForce GTX 650 Ti
USB 3.0 PCI-E card

I hope someone can help me out.

 

[rocktalkrock]

Those numbers don't look that bad to me. Keep in mind every USB thumb drive has a memory controller chip inside. At some point in the write process the memory controller chip just gets overloaded and has to slow down. Are you using a very expensive flash drive?

 

[styles2018]

Thank you for the quick reply.

If you're talking about the numbers on the screenshots I posted, yeah, they're good numbers. And these numbers are pretty accurate when I turn on my PC. However, at a random time those speeds will basically drop down in half. I'm not talking about speeds dropping down during the write process. They become low from the moment I begin the write process. The problem I see is that CrystalDiskMark always reports the same high numbers, both during and after these slowdown events.
And as I mentioned, it's not only USB Flash Drives. It's also copying between my internal hard drives, etc. I also checked to make sure. I tried to copy a 1.5 GB file from one HDD to another. At the beginning, when everything was normal, it took 15 seconds to copy the file. Now when I noticed this speed drop it took 30 seconds to copy the same file.

 

[rocktalkrock]

Thank you for the quick reply.

If you're talking about the numbers on the screenshots I posted, yeah, they're good numbers. And these numbers are pretty accurate when I turn on my PC. However, at a random time those speeds will basically drop down in half. I'm not talking about speeds dropping down during the write process. They become low from the moment I begin the write process. The problem I see is that CrystalDiskMark always reports the same high numbers, both during and after these slowdown events.
And as I mentioned, it's not only USB Flash Drives. It's also copying between my internal hard drives, etc. I also checked to make sure. I tried to copy a 1.5 GB file from one HDD to another. At the beginning, when everything was normal, it took 15 seconds to copy the file. Now when I noticed this speed drop it took 30 seconds to copy the same file.

1. Have you looked in Device Manager for any yellow warning signs?
2. Have you updated your motherboard with the latest SATA driver updates?
3. What is your power supply? Is it supplying enough power to all the parts in your system?

 

[styles2018]

1. Yes, I checked. No yellow warning signs.
2. If you mean AMD Sata Controller, it says the driver is up to date.
3. My PSU is Modecom Feel 2 500W. I've had it for almost 4 years now. I've never had any system restarts nor did any of my USB drives or peripheries ever lose power or disconnect in that time period.

I also have one question. Could the RAM be the culprit? As I mentioned, when transfer speeds fall down, there are also one second delays while doing simple stuff like saving documents in Word or saving images in IrfanView. Restarting Windows clears that problem.

I did only two passes in Memtest86 and it found no errors.

 

[rocktalkrock]

1. Yes, I checked. No yellow warning signs.
2. If you mean AMD Sata Controller, it says the driver is up to date.
3. My PSU is Modecom Feel 2 500W. I've had it for almost 4 years now. I've never had any system restarts nor did any of my USB drives or peripheries ever lose power or disconnect in that time period.

I also have one question. Could the RAM be the culprit? As I mentioned, when transfer speeds fall down, there are also one second delays while doing simple stuff like saving documents in Word or saving images in IrfanView. Restarting Windows clears that problem.

I did only two passes in Memtest86 and it found no errors.

1. I don't have any reason to think your Samsung RAM is a problem. 4GB is not a lot, but it should be enough.
2. The Sata driver update on your motherboards product page is "Version 3.2.1540.14 & 1.2.0.125 [2012/11/15]". Check the version and release date of your AMD Sata Controller. Is it newer, older or the same date?
3. I have never heard of Modecom Feel 2, but it's just a company label put on a PSU made in China. You don't know how good a power supply it really is. I don't think it's necessarily defective, probably just not a very good quality. It may not deliver as much power as it's 500watt label claims.

 

[mjslakeridge]

Check to see whether your HDDs need defragmenting.

 

[styles2018]

My version is newer. 5.2.2.179, Release date [2012/12/04]

So a weaker PSU may also affect the speed and not only whether a device is simply working or not?

And now I have another question. Like I said, I noticed these speed changes occur a month ago, but it may have been happening before that. The latest hardware change I made was about 6 months ago when my GPU fan died so I had to replace it. The fan is powered via Molex cable, it has 5V and 12V connector. I use 5V because I don't need it to blast full-speed. But it's connected to the PSU via Molex Y splitter cable and the other end of it is connected to my USB 3.0 card in PCI-E X1 slot. Maybe that doesn't give enough power and thus it slows down the transfer speed of my entire system in order for it to work? I don't know, I'm just guessing.

 

[rocktalkrock]

My version is newer. 5.2.2.179, Release date [2012/12/04]

So a weaker PSU may also affect the speed and not only whether a device is simply working or not?

And now I have another question. Like I said, I noticed these speed changes occur a month ago, but it may have been happening before that. The latest hardware change I made was about 6 months ago when my GPU fan died so I had to replace it. The fan is powered via Molex cable, it has 5V and 12V connector. I use 5V because I don't need it to blast full-speed. But it's connected to the PSU via Molex Y splitter cable and the other end of it is connected to my USB 3.0 card in PCI-E X1 slot. Maybe that doesn't give enough power and thus it slows down the transfer speed of my entire system in order for it to work? I don't know, I'm just guessing.

1. A low quality PSU can affect your PC in many ways, even if it does not cause it to crash. It may not be very good at keeping output voltages at a constant level. They can vary too much from the constant 5V and 12V they are supposed to deliver.
2. Whether a Molex Y splitter cable could be causing problems, i'm not really sure.
3. How good is your USB 3.0 PCI-E card? It has a controller chip on it as well. You should also check if the card has a firmware update.

 

[styles2018]

Okay, I believe I pinpointed where the problem in speed drop is. While things are normal, computer naturally allocates RAM for the copy process. So, I copy/paste something and my physical memory in Task Manager rises from, for example, 45 percent to 53 percent or something like that.

But right now, my speed dropped again and I tried to copy a file from one hard drive to another and it's not using any RAM at all. It stays at 45 percent.

So that's why the speed changes, I guess. Is this a RAM issue and should I simply buy new RAM or does something change in my Windows settings? How to fix this issue?

 

[rocktalkrock]

Okay, I believe I pinpointed where the problem in speed drop is. While things are normal, computer naturally allocates RAM for the copy process. So, I copy/paste something and my physical memory in Task Manager rises from, for example, 45 percent to 53 percent or something like that.

But right now, my speed dropped again and I tried to copy a file from one hard drive to another and it's not using any RAM at all. It stays at 45 percent.

So that's why the speed changes, I guess. Is this a RAM issue and should I simply buy new RAM or does something change in my Windows settings? How to fix this issue?

The first image you posted does show your C drive is 90% full. Freeing up more space may improve your computers performance. Also check the link below on Windows Virtual Memory Settings. It is what Window does when it run out of physical memory.

https://www.online-tech-tips.com/computer-tips/simple-ways-to-increase-your-computers-performace-configuring-the-paging-file/