AMD's marketshare is so low in servers that they can make a lot of gains even by addressing niches such as HPC, Berlin APU + GPGPU, and dense clusters, Seamicro acquisition + Cat family x86/64-bit ARM SoC. If those gain them just ~5-6% more over all server share then they've more than doubled their market presence.
AMD just does not have the management nor resources to compete head to head with Intel in the "traditional server market" and probably not in any market that doesn't value their GPU advantage or their willingness to offer lower priced product. Intel is in a different weight class than the rest of the competition due to maintaining the lead in fabrication. This won't change until Intel hits a fab wall that they can't spend their way past. There are already some signs that Intel may be slowing down in that regard due to market pressures (less Capex to power through on the fab side) and the increased technical difficulties of continuing to shrink transistors:
http://www.reuters.com/article/2013/07/17/intel-results-idUSL1N0FN20G20130717