The stock market ended mixed on the week, but held up very well, especially until the last 5-10 minutes when we had a sharp, quick sell-off into the end-of-month close.

The day started out with a gap up. They moved up sharply in the morning. The Nasdaq 100 went to new rally highs, but the S&P 500 failed to confirm at that point and sold off and retested but held. Then the indices stair-stepped their way back up towards the highs, making new highs on the Nasdaq 100 but once again not being able to confirm on the S&P. They tried it again late afternoon, broke through 2040 on the Nasdaq, again making new session highs but again not confirmed by the S&P. At that point they backed off into the close and then really spiked down in the last 5 minutes.

Net on the day the Dow slipped into negative territory by 8 points, and the S&P 500 managed to hang above 1400 at 1400.37, up 2.11. The Nasdaq 100 at 2032 had the biggest gain today, up 13.50, probably due chiefly to the Philadelphia Semiconductor Index (SOXX) having a terrific session, up 2 percent, or 8.36.

Technicals, however, were not terrific. Advance-declines were only 17 to 14 positive on New York and 16 to 13 positive on Nasdaq. Up/down volume was 7 to 6 positive on New York on total volume of a little over 1 2/3 billion. Nasdaq, on the other hand, had over 2 billion traded, with about a 2 to 1 positive ratio of advancing over declining volume.

TheTechTrader.com board had a very strong day with many point-plus gainers. By far the star of the day today was old favorite Energy Conversion Devices (ENER), soaring through 60 and getting as high as 64.55 before backing off on a little profit-taking, but hanging on to most of its gains, closing at 64.48, up 8.78 on 7 1/3 million shares, a new all-time high.

Other point plus gainers included Solarfun (SOLF), up 2.63 to 22.80 on 8 3/4 million. Canadian Solar (CSIQ) managed to gain 1.93 on 3 million shares, and JA Solar (JASO) jumped 1.03.

Broadcom (BRCM) up near its multi-month and 2008 high tagged 29, closing at 28.69, up 1.56. Portfolio position Digital Alley (DGLY) jumped 1.04 on a contract announcement, closing at 9.87, and another position of ours, Northern Oil & Gas (NOG), had an exceptional session, getting up to 11 3/4, closing at 11.54, up 1.04 today.

Shippers did well, with DryShips (DRYS) up 2.39 to 93.80, Excel Maritime (EXM) up 1.95 to 51.30, and TBS International (TBSI) up 1.39 to 46.58..

In addition, Former Chart of the Week GeoResources (GEOI) was up 1.32 in the strong junior oil sector.

On the downside, Sigma Designs (SIGM) got crushed for 3.41 after releasing a less than spectacular earnings report, closing at 18.50 on 6.8 million shares. That was the only point-plus loser on my board.

Stepping back and reviewing the hourly chart patterns, the indices did well after a strong week to hold most of their gains, except for the Dow, and except for a late pullback held support all session.

So we'll see if they can extend it next week or we get a rollover here, as the S&P 500 appears to be possibly developing a head-and-shoulders topping-type pattern. We'll see how it goes next week.

Harry Boxer is a technical consultant to many Wall Street hedge funds and large institutional traders, and author of TheTechTrader.com, a real-time diary of his day, swing and intermediate-term trades. For more of Harry Boxer, sign up for a free 15-day trial to his Real-Time Technical Trading Diary, or sign up for a free 30-day trial to his Top Charts of the Week service.