(Reuters) -Dell forecast fourth-quarter revenue below Wall Street expectations on Tuesday, weighed down by weaker demand for its traditional PCs and competition from rival server makers, sending its shares down more than 10% in extended trading. Despite booming demand for the company's AI-optimized servers used to handle large artificial intelligence workloads, Dell's PC segment has been grappling with stiff competition from rivals and weak consumer spending amid an uncertain economy. Enterprise customers are being mindful of their PC and IT spending in the short term, Dell executives said on a post-earnings conference call, adding that the company's consumer business was weaker than expected.