Waiting for a computer to boot up is one of the longest delays associated with normal computer use. Sure, rendering a video or running scientific calculations can take far more time - but not all users do those sorts of things, and even in those situations a computer can be used for other things while waiting... or you can go get a cup of coffee (or whatever your preferred beverage happens to be). Nothing can really be done during boot-up, though: the computer is not yet usable for anything else, but the time period is usually too short to make leaving your desk worthwhile.
Because of that, and partly also for bragging rights, having a short boot time is something lots of people have aimed for or hoped for. It seems intuitive that a more powerful processor and faster system drive would speed that up, but that is not always the case. To demonstrate, I put together a comparison of four systems from the time the power button is pressed until reaching the desktop. These are all running Windows 10, with the following core hardware:
Three systems with Asus Z170-A motherboards, Intel Core i7 sixth-generation "Skylake" processors, 16-32GB of RAM, and varying drives:
- Samsung 850 EVO SATA solid-state drive (SSD)
- Intel 750 PCI-Express SSD
- Western Digital Blue hard drive
As well as a fourth system, with dual Xeon E5 processors, 128GB of RAM, and a RAID 10 made up of four Samsung SSDs. Here is how they fared:
Despite having the same processor, the three similar systems have noticeable differences in boot speed... and it isn't just a case of the fastest drive winning. The Intel 750 SSD, on paper, is up to four times faster than the Samsung 850 EVO - but it finishes a few seconds later. That is because the actual hardware initialization takes longer, since it is a PCI-Express based drive. The 850 EVO uses a normal SATA interface, which lets it slide in ahead of the more advanced Intel drive.
The hard drive is far slower than either, which is to be expected since such drives have much lower overall performance. The hardware initialization doesn't necessarily take any longer than the Samsung drive, since both use SATA, but when it comes to actually loading Windows it takes a lot more time.
What will probably seem like an odd result to many, though, is the dual Xeon workstation. In pure, multi-core processing power it is well ahead of the others - and it has several times more memory. It also has what is a very fast drive array - coming close to the Intel 750 in read speeds, as measured from within Windows. But it takes more than twice as long to boot as any other system, and four times longer than the fastest one. Why is that?
Well, it all comes down to the amount of hardware that the Xeon build has to initialize. It has two processors, lots more memory, multiple network adapters and other I/O interfaces, and a dedicated RAID controller card. Just turning on and checking all that hardware takes time, and then once it gets to Windows itself there are also more drivers to load up before reaching the desktop. This is something that server admins and users of workstations like this are probably familiar with, but I've heard feedback from people getting their first dual CPU system and being really surprised about how long it takes to boot up. Even just putting a RAID controller card in a single CPU system can add substantially to the boot times. And don't get me started on how long *quad* CPU systems take...
So what is the takeaway here? More expensive hardware does not necessarily mean faster boot times - in fact, often the opposite is true. Thankfully most folks won't have to deal with booting up more than a couple times a day, but if for some reason your workload involves restarting more often then this is something to consider when spec'ing out a computer.
Also, when possible, I recommend using a sleep or standby mode. These put the computer in a low-power mode, generally turning off all hardware except the RAM and maybe network or USB ports. In such a state the computer draws almost as little electricity as if it were completely off, but it can resume in a matter of seconds. I didn't explicitly test it for this post, but I would say that most single CPU systems resume from Windows' sleep mode in about 2-3 seconds, and dual CPU systems come in at around 5-10 seconds. Far better than a cold boot, any way you look at it!