As amazing as it may sound for an IT professional of many years, aside from my work laptops, I do not own a Windows computer! For my personal computing requirements, I use a £200 Chromebook to connect to the internet and do most everything I need in the cloud.
My dear wife, on the other hand, is not a fan of the Chromebook and likes a ‘good old-fashioned’ Windows computer. But since her computing requirements are minimal, I decided to investigate the cost of running a Windows 10 VM in Azure instead of buying a new Windows laptop that she won’t use very often. Turns out, it’s quite a cost effective way to run a Windows 10 OS 🙂 The only things you really pay for are the disk storage and VM compute time. To access the VM, we simply use a remote desktop app on the Chromebook.
The first thing you need is an Azure subscription. Currently you get some credits for the first month, then some services that are free for the first 12 months. Even after that, if you have no resources in the subscription you won’t pay a penny for it.
You can create a Windows 10 VM from the Azure Marketplace. Creating the VM will create a few resources in a resource group such as a NIC, an NSG (network security group), a disk and of course the VM itself. To save on cost, I didn’t add any data disk and just used the 127GiB disk that comes with the OS. I also used the basic sku for the NSG, and I didn’t assign a static public IP address – I simply added a DNS name. You’ll get charged for a static IP (something like £0.06 p/day) but if you use a dynamic IP with a DNS name you won’t get charged anything.
For the disk, I somehow assumed that I would need a Premium SSD to get good performance as that’s what I would typically use for corporate VMs, but as this is for home use and I’m not really concerned about SLAs, I experimented with the Standard SSD and the Standard HDD as well. I was surprised to find the the Standard HDD was perfectly adequate for every day use and I didn’t really notice much difference in performance with either of the SSD options. Of course you do get less IOPS with an HDD, but that hasn’t been any issue. Since an HDD is much cheaper than an SSD, it made sense to use one.
For the VM size, I used an F4s_V2 which is compute optimized, has 8GB RAM, 4vCPUs and runs great. You could certainly get away with a smaller size though and shave your compute costs, something like a DS2_V3 and it’ll still run just fine.
In the tables below I summarized the actual costs of running the VM and also compared the costs of using Premium SSD/Standard SSD/Standard HDD. These costs are in GBP (£) and are in the UK South Azure region and are true at the time of writing – prices will vary based on region and currency and VM compute hours. The costs are also from actual invoiced costs – not from the Azure price calculator. The price calculator can give a good ball-park figure but in my experience the actual cost will be different…
Note: there are also data egress costs, ie data coming out of Azure. Downloads etc within the VM are ingress and don’t generally get charged. But even for egress you get the first 5GB free anyway (see here).
| Time period | Cost (£ GBP) |
|---|---|
| Per hour | 0.16 |
| Per day | 3.84 |
| Per month | 116.8 |
| Per year | 1401.6 |
| Time period | Cost (£ GBP) Premium SSD | Cost (£ GBP) Standard SSD | Cost (£ GBP) Standard HDD |
|---|---|---|---|
| Per day | 0.57 | 0.25 | 0.12 |
| Per month | 17.34 | 7.6 | 3.65 |
| Per year | 208.05 | 91.25 | 43.8 |
So the base cost for owning the VM is £3.65 p/month using a Standard HDD. On top of that is the compute time. For example, if I use the VM for 20 hours in a month, the compute cost is £3.20 for the month. Add that to the base cost, and it’s £6.85 for the month. That’s not bad 🙂
Some key things to remember are that you always pay for the disk storage whether you use the VM or not. You only pay for compute time when you actually turn on the VM and use it. Always remember to actually stop your VM when finished (not just shut down the OS) so that the resources are de-allocated and you are not charged for unnecessary compute time. Use the Auto-shutdown feature to ensure the VM gets stopped every night. Also, since you have a public IP address it’s a good idea to use some NSG rules to restrict who or from where and on which ports you can access your VM.
Using an Azure VM for personal computing needs is a great option – you benefit from the elasticity and scalability of the cloud, and you only pay for what you use. You can scale up or scale down at any time according to your needs and you can set a budget and keep your eye on how much you’re spending using Azure cost management.
