Nvidia has released updates today dealing with the issues. So I would assume there are risks since they have created updates.

http://us.download.nvidia.com/Windows/390.65/390.65-win10-win8-win7-desktop-release-notes.pdf

> Table 2.1 Security Updates for NVIDIA Software Vulnerabilities CVE ID
> NVIDIA Issue Number Description CVE-2017-5753 1975134 Computer systems
> with microprocessors utilizing speculative execution and branch
> prediction may allow unauthorized disclosure of information to an
> attacker with local user access via a side-channel analysis. For more
> information on this issue, see the NVIDIA GPU security updates for
> speculative side channel Security Bulletin posted on the NVIDIA
> Product Security page

And specifically mentions GeForce in the aforementioned post http://nvidia.custhelp.com/app/answers/detail/a_id/4611

    Affected Products

    Product	               | OS
    GeForce, Quadro, NVS   | Windows, Linux, FreeBSD, Solaris
    Tesla	               | Windows, Linux