BSOD - Sometimes NDIS.sys "driver_irql_not_less_or_equal"

It is display driver again, and I could suggest you to follow the post #8 again.

Hmm any idea why?

Should I try replace the card ? (or could you make any recommendations for an upgrade/on-par card?)

Since I think I'm limited by PSU which I could replace soonish

Have you pulled the GPU card out and replaced it to reseat it? That helps sometimes.

If you upgrade I would suggest a card with at least 1GB of GDDR5 with a 128 bit interface. Brand choice is your choice but I'd stay with nVIDIA since you have one now and it is difficult to get rid of all the drivers.

Then go by the recommendation of PSU for the card you get. Don't try to run a "bigger" card with 400W. I also recommend Corsair and Seasonic PSUs.

Your specs say your PSU is 400W your CPU is 95W. Intel Core 2 Quad Q8300 AT80580PJ0604MN / AT80580PJ0604ML (BX80580Q8300)

We'd need an exact model and make on the 440.

The 610 should be fine, it doesn't need any PCIe power connectors.

And, as it is problem free over a reasonable time, you should not be more worried now :)

Observe the performance of the computer, let us know how it is performing, is there any further issue or not.

You are welcome :)
Me and my friend Britton30 both are very happy that your issue is over :)
But if there is any further issue, let us know.