All 64-bit virtual machines require VT-x to virtualize x86_64, because isolation of the virtual machine would be impossible without it1.
So unless you buy a VT-x enabled CPU, you have only one solution, that is using an emulator such as Bochs or QEMU. But since everything is emulated, the speed is slow (or very slow) and may only suitable for not very heavy operations.
It's easier for Linux and other OSes with open-sourced kernel since you can use paravirtualization like Xen which may be even better in terms of performance compared to hardware-assisted solutions because of the low overhead. It modifies the kernel to work so unfortunately it's not available for Windows
Another alternative is to install a 64-bit OS and then run 32-bit guests inside it
Not sure if it's too late or not but hope it'll help you and any one with a CPU without VT-x.
The initial version of x86-64 (AMD64) did not allow for a software-only full virtualization due to the lack of segmentation support in long mode, which made the protection of the hypervisor's memory impossible, in particular, the protection of the trap handler that runs in the guest kernel address space.
Revision D and later 64-bit AMD processors (as a rule of thumb, those manufactured in 90 nm or less) added basic support for segmentation in long mode, making it possible to run 64-bit guests in 64-bit hosts via binary translation. Intel did not add segmentation support to its x86-64 implementation (Intel 64), making 64-bit software-only virtualization impossible on Intel CPUs, but Intel VT-x support makes 64-bit hardware assisted virtualization possible on the Intel platform