New PC is CTD During Games

Hi

I can help a bit with Skyrim, but not Sim City etc.

You're experiencing Bethesda bugs, from original game. If all you are looking for is to play Vanila version of Skyrim, then my recomendation is to wait until the remastered version is out (if not already, sorry I don't keep up on it so don't know the release date).

If you are modding Skyrim, then my advice is as follows:
1. Install Skyrim + all your Bethesda DLCs from Steam.
2. Disable and ditch the steam workshop mods with extreme prejudice as they are utter crap as is their steam installer.
3. Go to Nexus for your mods, and read up some stuff on the forums tehre 1st, before you plunge into it or you'll be just crashing with CTDs and reinstalling many, many, many times.
4. Learn and use all the Unofficial Patches and bugfixes for Skyrim. <<<<< This will give you a stable, not crashing game.
5. Branch out to other mod sites, especially lovers lab for your kinky mods, again, read up on everything 1st or you'll be doing even more crashes and re-installs.

Things of note:

The original skyrim and its DLCs are 32 bit and suffer from memory issues even further hampered by Win 10, as there are some work arounds for Win 7 64 bit, but those are unusable in WIn 10.

Your GPU has only 4 gigs of VRAM, which means even when you do get some of those workarounds to work, or the 64 bit version of Skyrim comes out, you will run out of VRAM. Period. I fill out my 4 GB of VRAM with just custom bodies with 4k textures + outfits + some extra NPCs real quick. When I scale down the body textures to 2k, my game becomes playable. And thats not even glancing at things such as ENBs or high res terrain or lighting features etc. With those in, its even worse.

With an 8GB VRAM GPU, I can at least have full amount up to the possible 4gb limit working for skyrim then anything else that requires vram can still run in the background. When I finally get around to playing it again, it will be the 64 bit version of the client that will have my full VRAM available for it, which is a beautiful thing.

One thing you can try is to reinstall the older versions of dot net and vcredist + direct X, but that may lead to other issues under windows 10 and mess up your system a bit.

If its modded Skyrim, go the mod forums, you'll get much more detailed and better info there.

Depends. If you're playing the 64 bit Skyrim on high / ultra high, then even vanila may choke on 4 GB. If you add mods to it, then definetly not. If you're playing the 32 bit then it will still choke, but it doesn't matter because of the Skyrim memory limitations, will be both for same versions unless you make one of your drives win 7 64 bit and use the memory tools for Skyrim.

As to for how and where and why, its a huge read and way more to type then I possibly have time, so you'll have to do your own research. Again, check out the Skyrim sites rather then here for Skyrim specific info, especially the ones I noted. You will need to devote some time to reading up on all this stuff and ask there.

Here, you will only get general gaming advice, which is ok in general, but sometimes at odds with Skyrim specific stuff.

As far as GPUs for Skyrim are concerned it goes like this 3GB < 4GB<6GB<8GB<12GB. 12 GB GPUs are of course in a price range of their own so vast majority of us will go with the ones below that. Again, the actual processing speed will do jack shit, for you when your game crashes or you cant use mods / features you want on it due to lack of VRAM.

When on the Skyrim forums just ask for some screenshots / vid links for when runnign out of VRAM so you have a good idea what it actually looks like, what it is, and to what point it will bother you.