TerraMaster Forum

Hi, last year before we realised that you shouldn't update TOS to 5.1.34 on 2gb of RAM I somehow managed to do it, it maybe because I'm using JBOD no RAID.
However I do occasionally experience a few issues such as very slow read/write speeds and was thinking of either going back to TOS 5 or even 4, either way is it possible to do without losing any data?
My NAS is a F2-221 4gb RAM.
Thanks

Perhaps you're referring to this?
viewtopic.php?t=4912
TOS 5 has no issues caused by RAM capacity. You may be talking about system partition capacity.
You can try to choose custom manual installation and use the TOS4 installation package.
However, please note that on the initialization webpage of the new version of TOS5, if there is a prompt of "delete/format", there may be storage exceptions. Please do not continue, otherwise you may lose data. If you encounter such a problem, please contact the technical support email or the customer service window on the official website to make an appointment for remote assistance.