Why is VPN making your laptop so slow?
Short answer: A VPN (Virtual Private Network) encrypts all your traffic and routes it through a remote server before it reaches the internet. This adds two sources of delay: encryption overhead on your laptop's CPU, and the physical distance to the VPN server. A VPN that drops your speed by more than 30% is fixable in most cases — the cause is usually the wrong protocol, a distant server, or full tunnelling routing non-work traffic unnecessarily.
How to fix slow VPN performance step by step
Step 1: Switch to WireGuard protocol
VPN protocols differ significantly in speed and CPU usage. OpenVPN — the most common protocol on older VPN clients — uses software-based AES encryption that can consume significant CPU cycles, especially on Intel Celeron or AMD Ryzen 3-series laptops common in the Indian mid-range market. WireGuard, a modern protocol supported by NordVPN, Surfshark, Mullvad, and others, uses hardware-accelerated encryption built into modern CPUs (ChaCha20 cipher). Switching from OpenVPN to WireGuard alone can improve throughput by 40–60% on the same server. In your VPN app settings, look for Protocol or Connection Type and select WireGuard.
Step 2: Enable split tunnelling
Full tunnelling — the default on most VPNs — routes all internet traffic through the encrypted VPN tunnel, including YouTube, Spotify, and general browsing that has nothing to do with your company network. This wastes VPN bandwidth and slows everything. Split tunnelling sends only work-specific traffic (your company intranet, internal tools, git repositories) through the VPN and routes everything else directly to the internet. Enable it in your VPN client: most apps have a Split Tunneling or App Exclusion section in settings. Exclude browsers, Teams meeting calls (video traffic is high-bandwidth), and streaming apps. This change alone can make a WFH setup feel dramatically faster.
Step 3: Choose the right server
In India, most ISPs (Airtel, Jio, BSNL) route international traffic through Mumbai or Chennai peering points, then on to Singapore or London. If your company VPN server is in Singapore, your traffic takes an optimal path. If it is in Los Angeles, every packet travels Mumbai > London or Singapore > LA and back — adding 200–300ms of round-trip latency that makes Teams calls choppy and file transfers slow. For personal VPNs, choose a server geographically close to your actual destination — a server in Singapore is better than one in the US if you are accessing a Mumbai-hosted service through a Singapore exit node.
Step 4: The India network angle — ISP throttling and MTU
Several Indian ISPs apply traffic shaping that throttles VPN connections during peak hours (7PM–11PM). The symptom is fast VPN in the morning and crawling speeds in the evening. One mitigation: change the VPN port to one not commonly throttled. NordVPN and Mullvad support connecting on port 443 (HTTPS), which is rarely throttled. Another hardware-level fix is setting the MTU (Maximum Transmission Unit — the packet size) on your VPN adapter. In Windows, open a CMD prompt as Administrator and run: netsh interface ipv4 set subinterface "Local Area Connection" mtu=1400 store=persistent. Oversized packets that hit VPN encapsulation overhead can fragment and cause throughput drops — reducing MTU to 1400 bytes prevents this. Also check: if the laptop is connected over Wi-Fi, a 5GHz band connection dramatically outperforms 2.4GHz for VPN workloads. See our related WiFi troubleshooting guide for improving the base wireless connection before tuning VPN.
When to call a laptop repair service (and what it costs in India)
When DIY ends
Slow VPN is almost never a hardware repair issue. The only hardware scenario: a failing or slow Wi-Fi adapter card that delivers degraded wireless throughput regardless of VPN. If your internet speed without VPN is also unusually slow compared to other devices on the same network, the Wi-Fi card may need replacement.
Typical repair cost in India
Wi-Fi card replacement (Intel AX210, MediaTek MT7921): ₹800–₹2,500. RAM upgrade (if the laptop is also slow in general — 8GB minimum for comfortable WFH use): ₹1,500–₹4,000. General service including thermal paste and cleaning (overheating from VPN CPU load): ₹800–₹2,000. Doorstep diagnosis: ₹149.
A note from the LRW Engineer Team
The most common WFH VPN complaint we hear is from users on Jio or BSNL broadband — connection speed tests show 100 Mbps but the VPN crawls at 5 Mbps. Almost always the fix is switching from OpenVPN TCP to WireGuard, and restricting the VPN to work traffic only with split tunnelling. The laptop hardware is not the bottleneck in these cases. Also see our Tailscale setup guide if you are looking for a WireGuard-based alternative to traditional corporate VPNs.