Just my 2 cents from repairing a multitude of HP and Dell servers. I would always go HP. The beep code/lights are far more informative than dell and are consistent throughout all the models I handled back in the day.
For example while with the Dells 1 beep on a r730 means RAM issue and on a R720 means a PSU. Cuz of that most the answers on the dell forum are wrong and you end up wasting endless time on the wrong thing. Best thing to do when troubleshooting Dells is get the manual of the model you have to identify the beep/light codes and ignore everything you read else where.