Oh, I was responding to 12GB RTX3060 on Windows using NVIDIA Developer driver (as apposed to the new HiveOS update) ... Didnt mean Windows developer.
Anyway, I get around 50MH/s on the RTX 3060's and am just finishing a 7 x RTX3060 rig ... a lot cheaper than RTX3070/3080 at the moment !

TREX is fine for RTX3060 using Windows Developer Unlock, I even dual mine with it:

Mining at eu1-zil.shardpool.io:3333, diff: 4.29 G
GPU #0: ASUS NVIDIA RTX 3070     - 62.28 MH/s, [T:60C, P:162W, F:60%, E:421kH/W], 23/23 R:0%
GPU #1: ASUS NVIDIA RTX 3070     - 62.28 MH/s, [T:57C, P:162W, F:60%, E:424kH/W], 23/23 R:0%
GPU #2: Gigabyte NVIDIA RTX 3070 - 61.92 MH/s, [T:56C, P:183W, F:60%, E:371kH/W], 15/15 R:0%
GPU #3: MSI NVIDIA RTX 3060      - 49.04 MH/s, [T:42C, P:110W, F:55%, E:486kH/W], 12/12 R:0%
Hashrate: 235.51 MH/s, Shares/min: 2.356 (Avr. 2.695), Avr.P: 563W, Avr.E: 418kH/W
Uptime: 27 mins 13 secs | Algo: ethash | T-Rex v0.20.4
WD: 27 mins 15 secs, shares: 73/73

Oh and just a reminder if you intend to hold both ETH + ZIL DAG in GPU memory, ETH is about 5GB, ZIL is close to 2GB, so 8GB cards are getting close to the limit (eg. RTX 3070) ... but 10GB cards (RTX 3080) or even 12GB cards (RTX 3060) no problem .... It's just that one of my 3070 rigs was reporting an out of memory problem with dual mining ZIL+ETH, yet another RIG with mixed 3060/3070 would DUAL mine fine ... I'm suspect as to if I have some dodgy video memory on one of the cards in the 3070 RIG.

Checkout the example batch file "ETH+ZIL-shardpool.bat", which works for shardpool.io for ZIL & ethermine for ETH... but I found some zil mining pools force you to also send eth mining to their pool.

Here's my windows batch file, username is your ethwallet address and you pass your ZIL wallet address to the ethermine as proxy, '-w crypto1' is your RIG or worker name if you track multiple mining rigs:

"t-rex.exe -a ethash -o stratum+tcp://eu1-zil.shardpool.io:3333 -u 0x9eee2abb7b781638f9ef66c37a0023b45c1ad422 -p zil1ynzy3d6euan9yt0jced4kvha8ct6fq9z6kzl07@eu1.ethermine.org:4444 -w crypto1 --extra-dag-epoch 0"

I have multiple RIGS doing this and can check ethermine.org website for eth mining details and shardpool.io for ZIL mining details.