--- title: Two Proxmox settings fixed the lag in my VMs, and the... description: Changing a Proxmox VM's CPU type from the default x86-64-v2-AES to 'host' exposes the host processor's full instruction set (AVX, AVX2, FMA, BMI), improving... canonical: https://daily.dev/posts/two-proxmox-settings-fixed-the-lag-in-my-vms-and-the-performance-difference-is-instant-a09l3s0c5 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Two Proxmox settings fixed the lag in my VMs, and the performance difference is instant | daily.dev og:description: Changing a Proxmox VM's CPU type from the default x86-64-v2-AES to 'host' exposes the host processor's full instruction set (AVX, AVX2, FMA, BMI), improving... og:url: https://daily.dev/posts/two-proxmox-settings-fixed-the-lag-in-my-vms-and-the-performance-difference-is-instant-a09l3s0c5 og:image: https://api.daily.dev/og/posts/a09l3s0c5.png og:image:alt: Two Proxmox settings fixed the lag in my VMs, and the performance difference is instant og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Two Proxmox settings fixed the lag in my VMs, and the performance difference is instant **[XDA Developers](https://daily.dev/sources/xda-developers)** · 4 min read · 0 upvotes · 0 comments ## Summary Changing a Proxmox VM's CPU type from the default x86-64-v2-AES to 'host' exposes the host processor's full instruction set (AVX, AVX2, FMA, BMI), improving performance for software-rendered graphics via Mesa, though this can hurt Windows 11 guests by triggering virtualization-based security. Switching the display from the default VGA/noVNC setup to SPICE (QXL paravirtualized graphics plus Remote Viewer) eliminates cursor lag and window smearing, and enables a shared clipboard when the SPICE agent runs in the guest. Proxmox's defaults prioritize compatibility and live-migration safety across clusters, so these tweaks are best suited to single-node home lab setups rather than production clusters; the x86-64-v3 CPU model is offered as a middle ground that adds AVX2 support while remaining portable across Broadwell-or-newer hardware. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### How do I fix laggy cursor and window dragging in a Proxmox VM viewed through noVNC? Switch the VM's display setting from the default VGA adapter to SPICE, which swaps the emulated card for QXL, a paravirtualized graphics device. This opens the console through Remote Viewer instead of the noVNC browser tab, making the cursor track properly and eliminating window smearing. Running the SPICE agent inside the guest also enables a shared clipboard. _daily.dev surfaces home lab tuning tips like this for anyone chasing smoother Proxmox VM performance._ ### Why does changing Proxmox VM CPU type to host improve performance, and when should I avoid it? Setting a Proxmox VM's CPU type to host exposes the guest to the full instruction set of the physical processor, such as AVX, AVX2, FMA, and BMI extensions, instead of the generic x86-64-v2-AES default modeled on an old Westmere chip. This speeds up software-rendered graphics via Mesa. Avoid it for Windows 11 guests, since it triggers virtualization-based security that hurts performance, and avoid it in clusters where VMs migrate between nodes with different CPUs. _Developers weighing VM configuration trade-offs can track practical Proxmox settings guidance on daily.dev._ ## Similar posts on daily.dev - [Every VM you have in Proxmox is pretending to run on an older CPU, and one dropdown fixes it](https://daily.dev/posts/every-vm-you-have-in-proxmox-is-pretending-to-run-on-an-older-cpu-and-one-dropdown-fixes-it-dlipix0au) · XDA Developers · 0 upvotes · 0 comments - [I thought my Proxmox server was slow until I changed this setting](https://daily.dev/posts/i-thought-my-proxmox-server-was-slow-until-i-changed-this-setting-9dtndv14c) · XDA Developers · 1 upvotes · 0 comments - [I always tweak my Proxmox host's settings before spinning up a single VM or LXC](https://daily.dev/posts/i-always-tweak-my-proxmox-host-s-settings-before-spinning-up-a-single-vm-or-lxc-j7bpwodpd) · XDA Developers · 0 upvotes · 0 comments - [Linux's KVM Preps For APX Support In VMs](https://daily.dev/posts/linux-s-kvm-preps-for-apx-support-in-vms-tnmzpxavq) · Phoronix · 1 upvotes · 0 comments - [Your Proxmox server can handle 10 times the workload if you stop treating everything like a virtual machine](https://daily.dev/posts/your-proxmox-server-can-handle-10-times-the-workload-if-you-stop-treating-everything-like-a-virtual--dlyllfspt) · XDA Developers · 1 upvotes · 0 comments --- Tags: [#infrastructure](https://daily.dev/tags/infrastructure), [#homelab](https://daily.dev/tags/homelab), [#proxmox](https://daily.dev/tags/proxmox) [View this post on daily.dev](https://daily.dev/posts/two-proxmox-settings-fixed-the-lag-in-my-vms-and-the-performance-difference-is-instant-a09l3s0c5) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"TechArticle","headline":"Two Proxmox settings fixed the lag in my VMs, and the performance difference is instant","url":"https://daily.dev/posts/two-proxmox-settings-fixed-the-lag-in-my-vms-and-the-performance-difference-is-instant-a09l3s0c5","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/two-proxmox-settings-fixed-the-lag-in-my-vms-and-the-performance-difference-is-instant-a09l3s0c5"},"datePublished":"2026-10-03T13:02:50.898Z","dateModified":"2026-10-03T13:03:15.559Z","description":"Changing a Proxmox VM's CPU type from the default x86-64-v2-AES to 'host' exposes the host processor's full instruction set (AVX, AVX2, FMA, BMI), improving...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/00f22add889ced9e9acc80e540bd5eab?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/00f22add889ced9e9acc80e540bd5eab?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"XDA Developers","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"XDA Developers","logo":"https://media.daily.dev/image/upload/s--kCg6yyAP--/f_auto,q_auto/v1774964407/logos/xda-developers?_a=BAMAMiWQ0","url":"https://daily.dev/sources/xda-developers"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/two-proxmox-settings-fixed-the-lag-in-my-vms-and-the-performance-difference-is-instant-a09l3s0c5","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"infrastructure,homelab,proxmox","timeRequired":"PT4M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"XDA Developers","item":"https://daily.dev/sources/xda-developers"},{"@type":"ListItem","position":3,"name":"Two Proxmox settings fixed the lag in my VMs, and the performance difference is instant"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/two-proxmox-settings-fixed-the-lag-in-my-vms-and-the-performance-difference-is-instant-a09l3s0c5#faq","mainEntity":[{"@type":"Question","name":"How do I fix laggy cursor and window dragging in a Proxmox VM viewed through noVNC?","acceptedAnswer":{"@type":"Answer","text":"Switch the VM's display setting from the default VGA adapter to SPICE, which swaps the emulated card for QXL, a paravirtualized graphics device. 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