Microsoft had issued updates for AMD devices, but has had to put the delivery of the patch on pause following a slew of complaints from customers on its customer support channels.
AMD said on the same day that the issue would affect mainly its decade-old Athlon X2 chips.
People complained their machines were unable to boot following the installation of the patch to protect against the CPU threats.
And Microsoft and AMD are working on the issue, but the fact that an unknown number of PC owners with AMD CPUs are going to have to wait to have their devices protected from the risky bug is incredibly disappointing.
AMD shares fell almost 4 percent in early trading on Wall Street, after rising almost 20 percent last week on hopes the software problem may allow AMD to wrest market share from rival Intel.
After several days of dodging questions about the performance impact of patches created to fix the Meltdown/Spectre chip design flaws, Microsoft acknowledged Tuesday morning that Windows Server is now slower for certain types of applications thanks to the patches. AMD said in its statement it expected Windows updates for its chips to roll out again shortly.
Meltdown and Spectre are two memory corruption flaws which could allow hackers to bypass operating systems and other security software to steal passwords or encryption keys, on most types of computers, phones and cloud-based servers.
The updates are part of emergency measures aimed at protecting computers and mobile devices from Meltdown and Specter chip design flaws that affect microprocessors made by AMD, Intel and Arm Holdings.
According to CNBC, AMD had said its chip designs were not vulnerable to Meltdown but one variant of the Spectre bug could be fixed using the Microsoft update, but now both the chipmaker and Microsoft are working in tandem to resolve the problem with the patch.
"Windows Server on any silicon, especially in any IO-intensive application, shows a more significant performance impact when you enable the mitigations to isolate untrusted code within a Windows Server instance", wrote Terry Myerson, executive vice president for the Windows and Devices group, in a blog post released Tuesday.