I have a limit of about $350-400 on spending money and I’ve been wanting an upgrade from my Dell Inspiron 3650 with an GPU GeForce GT 710 Upgrade, and most or all of my games are on steam.
Should I get a Steam Deck or an cheap gaming laptop/PC?
If that is the limit of your budget, then for playing games, I doubt you’ll be able to get a PC at that price that will perform any better than a Steam Deck.
That being said, I wouldn’t necessarily recommend a 64GB Steam Deck unless you plan on upgrading the internal storage, regardless of any MicroSD card you get. You might be able to find a used one with a 1TB SSD already swapped in for what you have available in your budget. If you wanted to do the swap yourself, you can get a new 64GB Deck and a 1TB ssd for around $415 plus tax, so keep that in mind when you go looking for used Steam Decks. I personally would consider a used 1TB swapped Steam Deck in good cosmetic/working condition for around the price of new 64GB model, and all the better if you can find one locally and test it out before buying.
For that price range, the Steam Deck is probably the best you’re going to get for a full system. The only decent upgrade is at the $700-800 range where you can get an RTX 3050 laptop.
On the other hand, if you’ve got the i7-6700 Inspiron, then you could extend the life a bit by going for a lower wattage GPU like a GTX 1630 which should be able to run on that mobo, but you should do some research on it just in case.
Gt710 is not an upgrade, but if you can upgrade a PC (depends on current specs) it would do better. Other wise you can’t find a better laptop/pc with the price of a steam deck