Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of IT company Hewlett-Packard (NYSE:HPQ) fell 10% today after taking a $8.8 billion charge related to its acquisition of British software specialist Autonomy last year.

So what: $5 billion of the charge is being tied to serious accounting improprieties that were found after a whistleblower came forward, dealing yet another big hit to the embattled HP. Several analysts remained bullish on the stock given its cheap valuation and CEO Meg Whitman's plan to reinvent the company amid declining PC sales, but the whopping writedown -- its second $8-billion-plus charge of the year -- is forcing many of them to finally throw in the towel.

Now what: HP expects full-year 2013 EPS in the range of $2.10 to $2.30, which is in line with its prior outlook. "Fiscal 2013 is going to be a fix-and-rebuild year for the company as critical changes to our organizational structure take hold," Whitman said in a conference call with analysts. "At the same time, we expect the underlying macro and industry headwinds to continue as we enter 2013." So while traders might be tempted to pounce on today's pullback for a short-term a bounce, there's just too much uncertainty surrounding HP to make it prudent long-term turnaround play.

Interested in more info on HP? Add it to your watchlist.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.