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JVNeumann

macrumors member
Original poster
Mar 23, 2017
85
26
So I'm looking to run Windows for the occasional bit of gaming, and am just wondering if anyone has a rough idea of how much of a performance hit I'd be taking by putting Bootcamp on a USB-C SSD rather than on my 2017 iMac SSD (i7, 580)?

I have other libraries I could probably offload onto the external if the gaming really really benefited from the internal SSD, but I'm just not clear on if that's the case. So if anyone's benchmarked it...
 
I run BootCamp on a 500Gb Samsung EVO 840 SSD in a Delock Thunderbolt enclosure connected to my 2017 iMac via an Apple Thunderbolt 2 to Thunderbolt 3 dongle. It runs beautifully.

You should experience no loss in performance in Windows gaming on an external SSD although I highly recommend Thunderbolt over USB as it both makes installation a lot easier and allows you to enable TRIM, the lack of which will likely eventually lead to decreased performance over time.
 
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I run BootCamp on a 500Gb Samsung EVO 840 SSD in a Delock Thunderbolt enclosure connected to my 2017 iMac via an Apple Thunderbolt 2 to Thunderbolt 3 dongle. It runs beautifully.

You should experience no loss in performance in Windows gaming on an external SSD although I highly recommend Thunderbolt over USB as it both makes installation a lot easier and allows you to enable TRIM, the lack of which will likely eventually lead to decreased performance over time.
I think I'm using the same drive, albeit with a different enclosure obviously. I had noticed when I was booting OSX from that drive a few months back that the startup speed was literally about 800% slower than the internal drive had been. I never really got to stress test it beyond running some Logic Pro though, so maybe the speed issue was limited to booting up.

As for TRIM, I remember reading mixed reviews about it on here so when I bought my SSD enclosure I just went with the safe UBS-C, as I could use it across more of my machines. Could you elaborate on what benefits switching to Thunderbolt would yield?
 
I think I'm using the same drive, albeit with a different enclosure obviously. I had noticed when I was booting OSX from that drive a few months back that the startup speed was literally about 800% slower than the internal drive had been. I never really got to stress test it beyond running some Logic Pro though, so maybe the speed issue was limited to booting up.

Were you booting OS X from a USB3 enclosure? Then it was likely the lack of TRIM that caused the slowdown. See this thread about a Samsung SSD installed internally in an iMac that didn't have TRIM enabled.

As for TRIM, I remember reading mixed reviews about it on here so when I bought my SSD enclosure I just went with the safe UBS-C, as I could use it across more of my machines. Could you elaborate on what benefits switching to Thunderbolt would yield?

Well, off the top of my head, TRIM support, the ability to update SSD firmware (not supported via USB) and far easier installation of Windows just to start.

I fully support (and use myself) USB3 HDDs for data/music/photo/video storage and backup. For running an OS, not so much.
 
Windows 10 doesn't officially support using an external USB drive as a boot / system drive. There are ways around it but I wouldn't recommend it to be honest.
Windows 10 does support TRIM over USB if the external drive or enclosure supports UASP (USB attached SCSI Protocol)
 
Can anyone recommend a good thunderbolt SSD (looking for a 250gb one) that would be ideal for installing windows on? I made a similar post in the windows forum here but still have yet to decide on an SSD. I'm also going to be using this for pretty much just gaming, just like the OP will be doing. Thanks!
 
Well, off the top of my head, TRIM support, the ability to update SSD firmware (not supported via USB) and far easier installation of Windows just to start.

I fully support (and use myself) USB3 HDDs for data/music/photo/video storage and backup. For running an OS, not so much.

Thank you, this is very helpful. I had initially intended the SSD for mostly the latter storage purposes, but am now considering it as an OS device. I had no idea Windows would work better on TRIM than USB-C - I figured that would be more of an OSX issue.

Is there any reason why that enclosure costs $85 when there are ones like this for less than $30? Am I missing something critical here?
 
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Thank you, this is very helpful. I had initially intended the SSD for mostly the latter storage purposes, but am now considering it as an OS device. I had no idea Windows would work better on TRIM than USB-C - I figured that would be more of an OSX issue.

Is there any reason why that enclosure costs $85 when there are ones like this for less than $30? Am I missing something critical here?

You can read more about TRIM here. It is not specific to any OS.

The $30 enclosure you linked to is USB3.1, not Thunderbolt. The 2017 iMac has two USB-C ports which support USB, including the newer USB 3.1 Gen. 2 (up to 10GB/sec) and Thunderbolt 3. It also has four standard USB 3 ports.

You can use an inexpensive USB3 enclosure with an SSD in any of the standard USB ports but as mentioned, you will not have TRIM support.

In addition to the $85 Thunderbolt enclosure you will need to purchase a Thunderbolt cable and an Apple Thunderbolt 2 to Thunderbolt 3 adapter since the 2017 iMac only has USB-C ports for Thunderbolt now.

In my opinion the extra expense is well worth it in the long run.
 
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The $30 enclosure you linked to is USB3.1, not Thunderbolt.

That's where I'm confused; it says in the description: "Interface: USB-C (Compatible with USB 3.1 and Thunderbolt 3). It is not compatible with Thunderbolt 2 or earlier."

A recent reviewer also said: "Works great, the only enclosure I found that worked perfect with the thunderbolt port of my Asus Zenbook Pro 501VW."

Yet it doesn't state that it's TB in the product title, and the price is way lower than normal TB enclosures...
 
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That's where I'm confused; it says in the description: "Interface: USB-C (Compatible with USB 3.1 and Thunderbolt 3). It is not compatible with Thunderbolt 2 or earlier."

I understand your confusion. In this case, USB-C refers to the connector on the iMac. This article might help you to understand it a little better. The $30 enclosure can connect to Thunderbolt 3 (USB-C) ports but the chipset in the enclosure is the ASM1351 which is USB 3.1 Gen 2, not Thunderbolt. It does support TRIM in Windows 10 via UASP (see posts #5 and #6 above) but that is not ideal.


Yes, he is connecting it to a USB-C Thunderbolt 3 port on his computer, but the enclosure itself is USB 3.1 Gen 2, not Thunderbolt.
 
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I understand your confusion. In this case, USB-C refers to the connector on the iMac. This article might help you to understand it a little better. The $30 enclosure can connect to Thunderbolt 3 (USB-C) ports but the chipset in the enclosure is the ASM1351 which is USB 3.1 Gen 2, not Thunderbolt. It does support TRIM in Windows 10 via UASP (see posts #5 and #6 above) but that is not ideal.

Thanks, I knew it was too good to be true. What a nuisance that I have to blow an additional hundred on this enclosure.
 
Thanks, I knew it was too good to be true. What a nuisance that I have to blow an additional hundred on this enclosure.

Well, you don't have to. ;) I do recommend it as a worthy investment for the long run but if you are only planning to use it for Windows and don't mind not being able to flash firmware updates and the extra hassles of getting BootCamp installed on a USB drive then it does have the UASP TRIM support. It might be worth saving the bucks if you are only going to be going into Windows for occasional gaming. It's a tough call.

If we were talking about running macOS off the external or Windows for daily usage it'd be a much stronger recommendation and easier decision.
 
but if you are only planning to use it for Windows and don't mind not being able to flash firmware updates and the extra hassles of getting BootCamp installed on a USB drive then it does have the UASP TRIM support. It might be worth saving the bucks if you are only going to be going into Windows for occasional gaming. It's a tough call.

Yeah, seems like that's what it boils down to. There's also the added hassle of a ~3 week wait for the enclosure to ship.

So am I able to partition an external drive as a quarter Windows and leave the rest as storage for my Mac? And is this Thunderbolt/TRIM going to affect that as well?
 
So am I able to partition an external drive as a quarter Windows and leave the rest as storage for my Mac? And is this Thunderbolt/TRIM going to affect that as well?

You could, but I personally wouldn't waste SSD space on storage. TRIM would not be as big of a concern in that application. I recommend investing in only as much SSD as you need for Windows.

As I mentioned above, cheap USB3-attached HDD is the most cost-effective way to go for storage/backup.
 
You could, but I personally wouldn't waste SSD space on storage. TRIM would not be as big of a concern in that application. I recommend investing in only as much SSD as you need for Windows.

As I mentioned above, cheap USB3-attached HDD is the most cost-effective way to go for storage/backup.

The reason I'm using an SSD for external libraries is basically twofold:

1. I needed a stand-in drive to run OSX from for a few months before my new iMac arrived, as my last iMac's drive died. I figured HDD would be agony, so I got an SSD, with the idea in the back of my mind that I might use it partly for running Windows/Steam from at some point.*
2. Drive speed is important even now that I'm no longer running OSX from it, because rather than keeping low priority files on there, I'm almost exclusively keeping VST libraries for Logic Pro. So read/write speeds actually need to be able to keep up. Seeing as things like batch re-saving libraries tends to increase performance speed a lot, I imagine SSD vs HDD would likewise have a strong impact.

*This brings me to another option, which is that I just allocate a few dozen GBs on my internal for Windows itself, but keep everything else on the external such as Steam etc.
 
2. Drive speed is important even now that I'm no longer running OSX from it, because rather than keeping low priority files on there, I'm almost exclusively keeping VST libraries for Logic Pro. So read/write speeds actually need to be able to keep up. Seeing as things like batch re-saving libraries tends to increase performance speed a lot, I imagine SSD vs HDD would likewise have a strong impact.

I don't personally use Logic Pro but from what I've read the main advantage of SSD over HDD, sustained throughput, is not really an issue with music production and particularly not for samples.

*This brings me to another option, which is that I just allocate a few dozen GBs on my internal for Windows itself, but keep everything else on the external such as Steam etc.

BootCamp will not be able to access (read/write) a Mac-formatted external drive.
 
I don't personally use Logic Pro but from what I've read the main advantage of SSD over HDD, sustained throughput, is not really an issue with music production and particularly not for samples.

While it's somewhat anecdotal, I've noticed that a lot of blogs and people I know who were saying that sort of thing around 2014/15 have changed their tune in the last couple of years, as library sizes have gone up and SSD prices have fallen. I haven't run any tests myself, but I've heard people say that after switching libraries away from SSD they had a hard time running larger files without the dreaded stuttering. And in another few years that'll probably be even more true, so I figured it'd be best to future-proof myself. Plus an SSD can always be used for other purposes such as running an OS, which I've already had to do once and may soon do again, so it's certainly paid for itself.

I don't personally use Logic Pro but from what I've read the BootCamp will not be able to access (read/write) a Mac-formatted external drive.
Can I partition and then format the partition? I figure that way at least I won't have to bother installing Windows in the external directly.
 
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