4.5GB of physical RAM. Will that cause a problem?
Funcionará bem, apenas possivelmente um pouco abaixo do ideal.
FYI Qual é a desvantagem de misturar RAM de tamanhos diferentes? módulos? e link :
Mixing different sizes of RAM bars makes the CPU cycle asymmetric, which can cause delay in the CPU’s data fetching that could become a bottleneck. However, this would not cause a problem of compatibility.