The Virginia House of Delegates voted 94 to 10 today to approve a tougher conflict-of-interest law that would cover members of the General Assembly, statewide officeholders and all candidates for state office.

Under the legislation, officeholders and candidates would be required to name all clients they represent before state agencies if the clients by pay them annual fees of $1,000 or more. They would also be required to list clients of business associates with whom they have a "close economic" relationship, such as partners in a law firm.

The measure now goes to the Senate, where its supporters consider chances for passage good.

The legislation apparently would affect about 15 of 140 members of the General Assembly, most lawyers, according to various estimates. Among those is the sponsor of the House bill, House Majority Leader James M. Thomson (D-Alexandria). Thomson, according to his most recent disclosure statement in December, appeared as a lawyer before state agencies on behalf of 19 clients who each paid his firm at least $1,000 annually.

Under the present state conflict-of-interest law, those covered do not have to name clients specifically, only the type of business that they represented, such as "banks" or "transportation."

Del. Richard R. G. Hobson (D-Alexandria), while saying he would vote for the bill, said it "troubled" him because he thought it would create "problems getting candidates to run for office."

Judy Goldberg, chief lobbyist for Common Cause in Northern Virginia, which has been working hard for the passage of the bill, said she was surprised it had encountered no serious opposition in earlier committee hearings.

While stronger than the present Virginia conflict law, the bill would still allow a disclosure statement less stringent than in Maryland, where officeholders must be more specific on outside-salaries and financial holdings.

Unlike in Maryland, no dollar amounts on salaries or holdings are required under the Virginia disclosure law, although some lawmakers voluntarily provide such information.

In other action yesterday, the House:

Passed, 95 to 0, a bill giving school systems more flexibility in meeting state standards on pupil-teacher classroom ratios. The bill, which now goes to the Senate, would establish a system-wide pupil-teacher ratio but permit a higher maximum in individual classrooms.

The average classroom ratio, under the House-passed bill, would go to 27-to-one his September, but the maximum could go as high as 32-to-one in an individual class. Under present law, the maximum in any classroom would be 28-to-1 next fall.

Fairfax County assistant superintendent of personnel services William J. Burkholder said in telephone interview that the legislation would save most of the extra $2 million that the county estimated it would have to spend to meet present standards next fall. However, the Fairfax school system, anticipating legislation such as the bill that passed today, had not budgeted the additional money to meet present standards.

Gave tentative approval to a bill that is intended to encourage doctors to write more prescriptions calling for use of cheaper generic drugs rather than the brand name compounds. Sponsor of the bill, Del. J. Samuel Glasscock (D-Suffolk), said the bill had the support of both doctors' and pharmacists' groups, although not drug manufacturers.

Del. Ray L. Garland (R-Roanoke) said he is "glad to see corrective surgery that would permit the use of generic drugs." But he said the bill's requirement that the prescribing doctor check one of two boxes on a prescription permitting a generic drug or insisting on a specific brand name "would militate against" use of generic drugs. But the House backed the Glasscock bill, 43 to 30, on a show of hands. The final vote is scheduled Wednesday.

Killed on a voice vote a bill that would have required school boards to advertise openings on their panels. Its sponsor, Del. Dorothy S. McDiarmid (D-Fairfax), said the bill would "open up to people the chance to give a little input" to the selection process. Last year the General Assembly defeated more far-ranging bills that would have permitted Arlington. Fairfax and Prince William counties to have elected school boards.

Gave preliminary approval to a bill that would permit by law what already often takes place in practice - wearing of T-shirts advertising beer or other alcoholic beverages. The bill would also legalize such advertising on bed lines, towels, curtains, umbrellas and other household goods.

"This is the only bill I've sponsored which I've been interviewed about on radio in my six years in the House," Del. Chester J. Stafford (R-Giles) told the assembled House with a note of exasperation.

In other action in the Capital, members of Fairfax County's Board of Supervisors threw their support to a proposed amendment that would temporarily exclude Fairfax County from legislation now before the Senate.That measure would end the statewide moratorium on annexation efforts by towns and cities of county property.