Giving serious consideration to more than two or three NFL games a week, against the spread, is madness.

This week, I'm touting eight, for a mythical $500 each.

They are St. Louis giving 4 1/2 over Washington, New England giving 3 1/2 over San Diego, Buffalo giving 2 over the New York Jets, Philadelphia giving 4 over the New York Giants, Miami giving 6 1/2 over Chicago, Tampa Bay giving 3 1/2 over Los Angeles, Denver giving 5 over Seattle and (Monday night) Dallas giving 3 over Cleveland.

Taking one game at a time:

The Cardinal losses have been to the last Super Bowl teams -- by a total of four points. The Redskin victories have been against the Giants and Detroit. St. Louis will run on the Redskins, with rookie Ottis Anderson having an excellent afternoon. Washington has a problem at middle linebacker.

Steve Grogan has a habit of passing poorly against the tougher teams. San Diego is tough. But I'll give him one more chance. The Chargers, 3-0, have yet to face an offense as balanced as the Patriots'. Twenty points will not be enough to win.

The Bills are 9-0-1 against the spread at home since Chuck Knox took charge. Few coaches prepare a team as thoroughly, game after game, as Knox does. Buffalo is on its way out of the AFC East cellar. If the Jets aren't careful, they'll fall in.

Philadelphia lost Bill Bergey for the season last Sunday in New Orleans. That's a cruel blow, but the Eagle defense is still solid, and the Giants are probably the saddest outfit in the league, offensively. Tony Franklin's barefoot kicking will help Philly, which beat New York, 23-17, in the season opener after leading 23-7.

Miami continues to progress under the master, Don Shula. Don Strock may have to take over for the injured Bob Griese, but the key to this game figures to be the Dolphin defense. It can hold Walter Payton in check. The Bears' passing game still leaves much to be desired despite the long-yardage completions last week against Dallas.

Tampa Bay returns home 3-0, riding an emotional high, ready to turn in their best effort of 1979. The Rams' attack has been sputtering. It should continue to do so for another week, what with the Buccaneers' young defensive front certain to pressure Pat Haden.

Denver is always a selection worth considering playing at home, when their lackluster offense is not overmatched by the visitors' defense. The Broncos should move the ball fairly well against the Seahawks. When that happens, the Denver defense is the difference against almost anybody, except Pittsburgh.

Cleveland was outplayed last Sunday in beating Baltimore, 13-10. The Browns also were a little lucky to defeat the Jets, 25-22, and Kansas City, 27-24. I don't believe in luck when a team plays Tom Landry. The Browns (3-0) will be way up for this one but Brian Sipe is much more likely to commit the key mistake than Roger Staubach. Now if Tony Dorsett will remember not to fumble . . .

In other games this week, Las Vegas lists Atlanta 3 1/2 over Detroit, Pittsburgh 13 1/2 over Baltimore, Minnesota 2 over Green Bay, Houston 3 over Cincinnati, Oakland and Kansas City even and San Francisco 2 over New Orleans.