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So I'm getting the irql_not_less_or_equal BSOD. I tried looking at the event viewer for potential causes, and cannot find any.

I also checked the CPU temperature in BIOS right after the error and that was fine.

I've tried 2 sets of RAM chips already, both give the issues.

The error doesn't happen happens daily, but many hours can pass and it won't happen, or only 10 minutes can pass and it might happen again.

By the way, just bought the parts and built the computer myself a couple of weeks ago.

How to debug the cause for this?

Hardware info:

  • Asus P6X58D PREMIUM motherboard
  • Intel core i7 930 quad core 2.8 ghz
  • Kingston 128 GB SSD 3 Gb/sec
  • Nvidia Geforce GTX 465 PNY Edition
  • Corsair 12 GB DDR3 1600 Mhz Ram
  • Windows 7 Ultimate
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The IRQL_NOT_LESS_OR_EQUAL error sometimes indicates bad RAM. Do you get an error code?

To check your RAM, download and burn a Memtest86+ ISO to a CD (if you don't know how to do this, the easiest way is to use ImgBurn)

Boot with the Memtest86+ CD, let the scan run (it may take 20-30 minutes). If it passes, your RAM is fine. If it fails, you have a bad stick of RAM. If you have more than one stick installed, run the scan on each stick individually to determine which one(s) are causing the problem.

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-1 Memtest86+ continues running until explicitly stopped. Most people recommend running Memtest86+ for at least 5 passes, preferably overnight. – Hello71 Aug 16 '10 at 21:59
I've never needed more than one pass. The test is very thorough. – Force Flow Aug 16 '10 at 22:03

Sometimes though, especially with the IRQL_NOT_LESS_OR_EQUAL error, even that is not enough. This is where you get hardcore with the troubleshooting. In the BIOS, load Fail-Safe defaults, disable the onboard modem, sound, and LAN (where applicable). Take out all the cards, with the exception of video, and run the machine for a while. If the machine stays stable, then start adding/re-enabling the devices one by one. Keep in mind that modern motherboards share IRQ's across PCI slots, so try not to put a sound card and a modem right next to each other. They don't seem to think that's funny every once and a while. Anyway, do this one by one until you start crashing again. Whatever you put in last is the culprit.

Source: Tweaks for Geeks

The tricky part about this particular troubleshooting is it's getting difficult to disable everything in the motherboard and still run the computer. I used to have an OLD compaq that had a really weird bridging on the motherboard. It took me months to figure out what was going on, but this process was how I eventually found it. Congratulations, you are running into one of the most difficult BSOD errors to pin down :(

I would also make sure you are updated to the latest BIOS.

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IRQL_NOT_LESS_OR_EQUAL has exactly nothing to do with shared IRQs. And by the way, IRQ (actually INTx) sharing is a way of life on PCI. Also by the way, PCI devices that are next to each other are quite likely to not use the same INTx line. – Jamie Hanrahan Nov 7 '15 at 6:20

I just went through this...

In my case I went to the Event Log (system and application), and looked through all errors reporting since boot up time. And I just took them one by one...

Ended up finally being a sound driver.

One thing you can do is uninstall things from Device Manager and reinstall drivers. That brute force method might, in the end, be quicker than trying to debug this thing.

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Apropos RAM: I have had computers in the past where the memory timings were improperly set by the BIOS when left on auto, resulting in the IRQL_NOT_LESS_OR_EQUAL error. The solution was to manually set the CAS latency. You might try setting it manually to a slightly higher latency. The performance impact will be minimal/undetectable.

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