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How do I diagnose & fix a randomly slow laptop. I have a Compaq laptop that's already 2 years old. I have recently replaced its hard drive because I thought that it was dying and that's why its running slow. But after about 1 week of using the laptop with the new hard drive, it became slow again. I have installed Windows 7 on it. And its slow in every possible aspect that you could think of:

  • Booting
  • File transfer
  • The sounds aren't in sync with the display
  • Lagging

I also noticed that when the laptop gets slow, the hard drive activity(light) is blinking frequently.

I don't also think that I'm infected with virus/malware because its running perfectly for about 4 days up to 1 week. Then it will slow down again. Then after about 1 day-1 week of not using it. It will go back again to its previous state.

Tried checking the RAM about 3x already using the built-in memory checker and it detected no problems.

I don't also think that its a heat problem because I have cooling pads. And when I try to feel the bottom of the laptop, its not hot.

Things that I have notice while its running perfectly:

  • Acronis drive monitor always reports that hard disk temp is above 109 degrees F Whenever I try to watch my downloaded videos.-
  • Hard disk gets even more hotter than the CPU-


  • 2Gb RAM
  • 2.50Ghz core 2 duo Processor--
  • 320Gb traditional hard drive(hitachi)-
  • Integrated graphics card-

What other things could I try to solve this one? Please correct me if my belief isn't true?

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You gave us absolutely no information about the hardware of this laptop. Let's start there.. – Joe Philllips Nov 8 '10 at 17:30
sorry about that, I have now included the hardware info. – Ieyasu Sawada Nov 10 '10 at 2:32

When the hard drive light is unexpectedly "blinking like hell" I use task manager to see what processes are most active.

The SysInternals programs, such as FileMon, can also help identify programs that are doing a lot of disk IO.

Even though you don't think it is virus/malware, I would make sure I had a AV program installed and running.

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yep I have avast free running & updated, I think that's enough along with common sense & web of trust browser extension? – Ieyasu Sawada Nov 8 '10 at 11:14
When things get wonky on clients' computers, we always hit them up with ComboFix, MalwareBytes, Hitman Pro and SuperAntiSpyware, just to be on the safe side. – eidylon Nov 10 '10 at 3:15

Check your page file, and try defragging. Excessive hard drive use may indicate extreme fragmentation since it will constantly be seeking or an insufficient page file size. Best practice for this situation would be to set the page file minimum size to twice the size of your currently installed memory, the max should be double the minimum. Let me know if you need help finding and modifying your page file size.

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That drive temp is as good as off the chart. It may simply be a red herring, but it is worth further investigation. I'd advise you try an app like HDTune to check your SMART stats - a failing drive might be the problem.

Beyond that you might want to try using the built-in Win7 Performance Monitor to track the problem, and perhaps take a look at FileMon and ProcessMon to find out exactly what app/process is causing the problem. One thing you need to check is that you have enough RAM - if you don't, the machine will have to lean back on it's swap file which will mean intensive disk I/O. If you suspect this is the case, if you have a reasonably decent USB disk, you can use ReadyBoost to help improve the situation, though a RAM upgrade/replacement would be preferable.

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If the HDD light is going crazy, then it could be some processes like indexing, superfetch etc competing for disk resources with other applications simultaneously. Would it cause temperatures to hit 109

File fragmentation could also be a cause of slow performance, especially bootup times. Might want to defrag the files on the drive including system files such as the MFT (if fragmented). There are very competent commercial automatic defraggers that do these things automatically, and these utilities also have free trial versions, so you can grab one of those for the time being.

One more possibility is that the drive is reverting to PIO mode instead of UDMA, which would explain the very slow drive performance. However that doesn't explain the fact that it seems to work fine some of the time. If it's in PIO mode (check under IDE channels in Device Manager) it'll show consistently poor performance until you switch it back to UDMA manually.

BTW 42 C (109 F) is well within operational limits I think..IIRC max safe temperatures are around 60 C for most HDDs.

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It could well be that the antivirus program you are using is set to scan the drive on a daily/weekly basis and as "when the laptop gets slow, the hard drive activity(light) is blinking like hell" I would take a look at your antivirus program.

See if there is a scheduled task to do a full scan that is set to run on a weekly or daily basis and disable it to see if that helps. If you do so, remember that occasionally it is worth doing a full scan yourself to make sure all is well.

A full hard drive scan would cause a lot of operations on the hard drive and so could well be the reason it is getting hot.

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