The invention relates to a single-ended discharge lamp with circuitry in its housing base. The discharge lamp includes a discharge tube and a housing. The discharge tube is provided with electrodes containing a fill and sealed in a gas-tight manner. The housing base contains circuitry mounted on a circuit board and providing for the operation of the discharge tube. The housing base is built from two parts, a base and a cap, fixed to each other. The housing base is formed in a way suitable for mechanical and electrical connection to a lamp socket on one part, and for mechanically fixing the discharge tube and connecting the output terminals of the circuitry to the electrode inleads of the discharge tube on the other part. The circuit board is inserted between supports formed in the inside of and protruding from one part of the housing base. One feature of the invention is that longitudinal ribs are formed on the support and protrude from the support. The ribs are so dimensioned that in the direction of insertion of the circuit board, the space available for the circuit board progressively decreases, which results in the circuit board moving up to a stop on the ribs over at least a part of the length thereof.