diff --git a/repos/base/src/core/ram_dataspace_factory.cc b/repos/base/src/core/ram_dataspace_factory.cc
index 04911289a0..691b9f1b6a 100644
--- a/repos/base/src/core/ram_dataspace_factory.cc
+++ b/repos/base/src/core/ram_dataspace_factory.cc
@@ -40,16 +40,24 @@ Ram_dataspace_factory::try_alloc(size_t ds_size, Cache cache)
 	 */
 	Range_allocator::Alloc_result allocated_range = Allocator::Alloc_error::DENIED;
 
-	/*
-	 * If no physical constraint exists, try to allocate physical memory at
-	 * high locations (3G for 32-bit / 4G for 64-bit platforms) in order to
-	 * preserve lower physical regions for device drivers, which may have DMA
-	 * constraints.
-	 */
-	if (_phys_range.start == 0 && _phys_range.end == ~0UL) {
+	/* apply constraints */
+	if (_phys_range.start != 0 || _phys_range.end != ~0UL) {
+		for (size_t align_log2 = log2(ds_size); align_log2 >= 12; align_log2--) {
+			allocated_range = _phys_alloc.alloc_aligned(ds_size, (unsigned)align_log2, _phys_range);
+			if (allocated_range.ok())
+				break;
+		}
+	}
 
+	/*
+	 * If no physical constraint exists or constraints failed, try to allocate
+	 * physical memory at high locations (3G for 32-bit / 4G for 64-bit platforms)
+	 * in order to preserve lower physical regions for device drivers, which may
+	 * have DMA constraints.
+	 */
+	if (!allocated_range.ok()) {
 		addr_t     const high_start = (sizeof(void *) == 4 ? 3UL : 4UL) << 30;
-		Phys_range const range { .start = high_start, .end = _phys_range.end };
+		Phys_range const range { .start = high_start, .end = ~0UL };
 
 		for (size_t align_log2 = log2(ds_size); align_log2 >= 12; align_log2--) {
 			allocated_range = _phys_alloc.alloc_aligned(ds_size, (unsigned)align_log2, range);
@@ -58,7 +66,7 @@ Ram_dataspace_factory::try_alloc(size_t ds_size, Cache cache)
 		}
 	}
 
-	/* apply constraints, or retry if larger memory allocation failed */
+	/* retry if larger non-constrained memory allocation failed */
 	if (!allocated_range.ok()) {
 		for (size_t align_log2 = log2(ds_size); align_log2 >= 12; align_log2--) {
 			allocated_range = _phys_alloc.alloc_aligned(ds_size, (unsigned)align_log2, _phys_range);