Vanguard on Wednesday morning lowered the minimum initial investments for the low-cost Admiral Share classes of more than 50 active and passive funds. It dropped the ante for broad market index fund Admiral Shares to $10,000 from $100,000. Many of Vanguard's actively managed stock and bond funds also lowered their Admiral Shares minimums to $50,000 from $100,000.

The news means big savings for investors. For example, Admiral Shares of Vanguard Total Stock Market Index (NASDAQ:VTSAX - News) charge a rock-bottom fee of 0.07%, while Investor Shares with a minimum investment of $3,000 cost 0.18%. Fees for the Admiral Shares narrowly eke past Schwab Total Stock Market Index (NASDAQ:SWTSX - News), which last year lowered its expense ratio to 0.09% (after fee waivers) and has a minimum investment of $100. Meanwhile, Fidelity Spartan Total Market Index (NASDAQ:FSTMX - News) has a minimum investment of $10,000 and charges 0.10%.

The cost savings are similarly strong with Vanguard Total Bond Market Index VBTLX, where the Admiral Shares cost 0.12%, and the Investor Shares charge 0.22%. Another noteworthy difference is Vanguard Wellington Admiral Shares (NASDAQ:VWENX - News), which cost 0.23% compared with the 0.34% fee on Investor Shares.

While a $10,000 hurdle on index funds and $50,000 for active funds is steep for many investors, Vanguard says nearly half their individual investor client base should now qualify for the Admiral Shares. Investors rolling over assets from employer 401(k) plans may find the lower minimums more attractive.

Stocks fell Monday as investors took a pause from a historic rally in September and held back ahead of a busy week of economic and earnings reports.

The Dow Jones industrial average fell about 100 points in midday trading after a report showed factory orders fell slightly more than expected in August, but pending home sales rose a bit more than forecast.

Analysts say the market was due for a pullback following a 10.4 percent gain in the Dow last month. The monthlong rally has come on relatively low volume, a sign that many investors are still waiting on the sidelines.

Doug Roberts, chief investment strategist at Channel Capital Research, said the market has been trading in a broad range over the past six months. And with it approaching the high end of that range, a pullback is natural.

The market has been "alternating between euphoria and despair," Roberts said of the wide trading range dating back to late April, when stocks hit their high for the year.

This week brings a number of potentially important news events for stocks, including the monthly jobs survey on Friday and earnings from Dow component Alcoa Inc. on Thursday, the traditional kickoff to the quarterly earnings season.

PC and semiconductor stocks face trouble as sales growth slows. Warnings from Intel, National Semi, PMC-Sierra worry investors.

Earnings warnings from the chip industry have started to pile up. In late August, Intel cut its third-quarter sales guidance, cautioning that "revenue is being affected by weaker-than-expected demand for consumer PCs in mature markets." Not long after, there was a similar pre-announcement from National Semiconductor, which in early September said that "in the near term, slower growth in our end markets and distribution channel, along with some likely inventory reduction, will mute the seasonal growth that we would normally see in our business during this time of the year."

There were warnings earlier this month, as well, from Monolithic Power Systems and Silicon Laboratories. Last week, PMC-Sierra, known mostly for selling chips to the communications sector, cut third-quarter guidance with little explanation. Thursday afternoon, Advanced Micro Devices warned third-quarter revenue would be 1% to 4% below that of the second quarter, "due to weaker than expected demand, particularly in the consumer notebook market in Western Europe and North America."

So, is the worst over? I doubt it. CreditSights analysts Ping Zhao and Jordan Chalfin noted in a commentary last week that inventory in a number of sectors—including semiconductors, storage, PCs and distribution—has been ratcheting steadily higher. The analysts report that most tech sectors saw second-quarter inventory days rise from first-quarter levels—the opposite of the pattern a year earlier. The CreditSights analysts are particularly concerned about rising inventory at electronics distributors, warning that "any distribution inventory correction could have a negative impact to semiconductor companies' margins."

An energy trading firm has agreed to pay a $6 million fine to settle federal regulators' charges of misleading an exchange by failing to disclose facts concerning its relationship with a subsidiary.

The Commodity Futures Trading Commission, which announced the settlement Tuesday, said the withholding of information by Houston-based Vitol Inc. and Vitol Capital Management Ltd. caused the New York Mercantile Exchange to fail to add their market positions together. Combining their positions would have put the firms over the exchange's limits on the amount of future contracts that can be held by a firm at a given time, the CFTC said.

The two firms neither admitted nor denied the charges. Vitol Inc. is the U.S. subsidiary of Vitol SA, a privately held company based in Geneva, Switzerland, that is one of the world's biggest energy traders.

Vitol trades energy commodities and engages in trading in energy futures and options on the NYMEX as a hedging strategy. Vitol Capital Management trades in energy derivatives as well as futures and options, according to the CFTC.

The two firms did their trading separately but shared market information and should have reported their market positions together, the agency said. The firms learned in June 2007 that the NYMEX had an inaccurate perception of their relationship, the CFTC alleged. Rather than correct the perception, it said, the firms put in only "limited barriers" to prevent the flow of trading information between them. They "willfully failed to disclose to the NYMEX the true nature of the firms' relationship," the CFTC said in a news release.