Topic: 1.5TB SD Card Concerns

I decided to invest/impulse purchase the 1.5TB SanDisk Ultra microSD... directly from Western Digital, I feel is relevant to exclaim that I have no reason to doubt the memory card to be 'genuine'.
With that said; I have noticed a reduction in performance of my Switch in general since installing the 1.5TB card.
Before this I was using the 1TB version of the same brand card and didn't really notice any issues, or differences in loading speeds compared to the 512GB card before that...
I've upgraded my Switch's storage quite a few times since I first got it.
I knew going into using the 1.5TB card that I may encounter some performance issues, but I have always though that the hardware in the Switch wasn't capable of utilising the theoretical maximum speeds any of the cards I've used so far should be capable of anyway, so I have never given it any thought.
But, as you may be able to tell from my making this post; I am a little concerned about the unignorable drop in performance I have encountered with this latest upgrade.

I'm not completely fully versed in storage devices, and have always relied on the advice of others for my knowledge in this subject.
However, due to the rarity of information on using the current highest capacity storage in the Switch I am unable to diagnose the cause of my issues, or accept that this is normal behaviour with my specific combination of devices.

My question is of a technical nature, and hope someone who knows about this subject can chime-in and offer some insight into weather the behaviour is normal and acceptable, or it can be changed to improve things.

Specifically would formatting my 1.5TB card with a different cluster size make a difference?
Currently it is set at exFAT with a cluster size of 512 kilobytes... as formatted by the Switch itself.
If I were to increase (or decrease) the cluster size by reformatting it on my PC, would that do anything productive?

Currently the performance of my Switch is pretty slow... not unusable... but not great.
And if I am downloading and running a game at the same time loading times are quite significantly increased, especially when starting game up from the consoles main menu.
Also, the "All Software" menu takes quite a lot longer to open and populate the icons than with any other memory card I have used before this one.

Any advice or just confirmation that my Switch is behaving as it should in my particular setup would be greatly appreciated.

Thanks in advance.

I forgot to mention a couple of details:

Firstly; my Switch is not modified.
It's just a regular retail console (Mario Red & Blue Edition) I purchased from Nintendo directly.

Also, the download speeds aren't constant.
If I access the download progress of an actively downloading title the estimated completion time changes a lot, and sometimes the progress bar moves quickly and then slows again sometimes as though it isn't moving at all.
But, I know the Switch is downloading data because if my console is docked I have a USB Ethernet adapter and I can see the access LED working when it is.

I didn't know if that information would be useful to anyone who has thoughts on the subject, but it's there if it is.

A game's load speed, I think, is a reflection of the card's read speed, no?

Eshop servers are not always consistent. Game downlaods can be delayed or can be slower if there's a lot of server traffic. Late at night typically has more consistent download speeds, I think.

I was thinking the something like that.

And if the current 1.5TB card design is the cause, and this is normal behaviour; I can accept that.
I was just curious, because I didn't experience such degraded performance with the 1TB option.
Maybe the density of the electronics is significantly more of an effect on the performance than I estimated.

Although 1,649,267,441,664 bytes of data storage capacity is an astonishingly large amount for something the size of my fingernail.
And I also know that the write speeds of the 1.5TB memory cards are really low.

Thank you for your thoughts.

I am still curious if anyone has any experience or insight about the cluster size, or if messing with that setting will affect anything.
I've been living with this memory card for a few weeks now, and I'd rather not waste the literal days of downloading it took to get all of my content on it again... which re-formatting to change the cluster size will inevitably result in.

I'm not sure about the 1.5 TB cards - I did experience a strange issue with a 512gb card. It worked great for about a year or so, and then stopped loading games or taking forever to boot up, followed by horrendous load speeds in game. I formatted, and all worked fine. I recently upgraded to a 1 tb card, no issues. Did you format the card first? I am far from an expert here, just sharing something that helped me.

Different cards have different speeds. Nothing to do with capacity. For Switch you want something that says V30 on the card

Just adding in my experience here on this, I had played a long time on a SanDisk ultra 1tb card and also thought there should be no different going from the 190mbps of the ultra down to a SanDisk 150mbps 1.5tb card but wow.... Loading up a save in tears of the kingdom went from being a 10 second matter up to around 30 seconds and it's not just loading that's a problem from this card, if you go from the overworld down into the depths you can even have it where the depths do not load up fast enough and link will just be frozen in the air for a few seconds before they pop in around him. It's very jarring to the immersion of the game.

I moved totk Back to the system memory for now and it's night and day different. Sad to go back to my 1tb card and I guess I'll stick the 1.5tb in the steam deck and hope it has more to do with the combo of card and switch.

So piggyback to what's worth to buy.

SanDisk 1TB Extreme vs 1TB ultra? The price right now is ~10usd difference. Will I really see the difference?

@Switchforce it might not impact every game the same but like.... For the sake of 10 dollars if you have a TB worth of switch games that's gonna be several hundred worth. Also consider the switch 2 will likely also use micro SD cards and make more use of the higher transfer speed so you could move the faster card to the new machine.

Going from c10 to c30 means 3 times more data transfer speed maintained so it's really worth it for such a small difference.

I'm currently in the process of reverting back from my ultra 1.5tb to my extreme 1tb so yeah... Absolutely go extreme.

@Stormcloudlive, For Switch 2, I will get the 2tb card sandisk extreme if the price is right since that would have the 4k/dlss chipset that would be where to spend the money.

@switchforce sounds like a good plan for the future.

Been playing some master chief collection on the steam deck and a few GameCube games on the Odin 2 turned up to 4x resolution those 2 can really show how much the switch is in need of that hardware upgrade.

I see when they hit Holiday sales then I look into to doing a upgrade to extreme.

So if one gets the 1tb the spec should be "U3, CLASS 10, A2, V30" is this correct? I know the 2tb from Amazon is this "C10, U3, V30". So I guess these are the specs to look for then? I got the 1tb from samsung with SAMSUNG EVO Select microSDMemory Card + Adapter, 1TB microSDXC, Up-to 160 MB/s, 4K UHD, UHS-I, C10, U3, V30, A2.
https://www.amazon.com/dp/B0CWPNR918/?coliid=I1DWACDRA0QUKQ&a...

So did I buy the right one here?

Update here from my experience, so before sending the 1.5tb off to the Steam deck and putting the 1tb extreme card back in the Switch I figured I would try a few things to see if I could make it a bit more functional, tried a few different settings and such found online with little change to the incredibly long loading times in Zelda and non functional texture streaming in GTA3 but.... then I decided to see how the PC was formatting the smaller cards and what was different between that and the large card. (to clarify, I did also try using the Switch itself to format the 1.5tb card with zero improvement to the performance of it) but I noticed that the default file allocation size on the smaller cards was maxing out at 128kb where the default on the 1.5tb card was set to 512kb so I said I would try and change the larger card to use the 128kb file allocation size and BAM absolute night and day difference between the two. I started to re download my library to make sure it wasn't just down to having few files on there but now I've got the card almost filled at 1.3tb in use and Tears of the Kingdom still loads just the same as if it was stored on the 64bg internal storage and the likes of GTA3 texture streaming works flawlessly (or as good as that game manages lol) but yeah, so so happy I messed around with a few different types and hope this helps even one other person who spent money on a large SD card.

Just windows file explorer, format the card and change the default allocation size down to 128kb or at least something less than 512kb, still leave it at exFAT and pop it back into the Switch. Let me know if anyone tries this and gets a boost back to functional state.