I'll start at the beginning, I was born a long time ago on a farm, out in the wild... okay that might be going back too far... While using patch 1.5.0 I was getting frequent crashes sometimes every 5 to 15 minutes (some days, and then some days none) and lately I've only had one crash in probably close to 25 hours of play. Now I admit that I have also updated to 1.5.1 so that could have stopped my crashes but I started using these 'techniques' a few days before I updated to 1.5.1 (and I didn't crash then) so I'll still put this info up just in case it helps someone else. (Anything in brackets () means this is just editional info and can be skipped)

1. Don't leave the Ubisoft launcher up when you're not playing or don't plan to play for a while (if it's been open for ages a simple restarting might help too)
2. Once you get past the splash screens (where it says "press any key/press A to start") leave it for a minute before pressing the button, this is especially important if you've restarted your PC since last playing. (this is to given it time to finish loading the main 'framework' of the game. I'm not a programmer so I can't explain it well but when you restart your pc any temp files a game has in use will be cleared on a restart, (Dragon Age Inquisition is a good example of this as it takes longer to load the game after a restart) so giving it more time is basically letting the game finish doing its thing in case it needs additional time)
3. Give it 10 seconds before making a save in-game. (Skyrim taught me that games have scripts and things running in the background, (which can cause problems in your save if these aren't allowed to finish or mess up in some way) so I got into the habit of stopping my character from moving, making sure nothing is about to attack me, and then saving, again, this only takes about 5 to 10 seconds, basically you want to limit things loading in the background as much as possible).
4. Don't QuickSave Immediatley after leaving a menu (start menu, map, inventory etc) (This is because as you've probably noticed this game's ambient sounds take a couple of seconds to start after you leave a menu, and, as mentioned above I like to give a little time for things to settle before saving)
5. Try not to rely on AutoSaves (As alluded to above I don't like the idea of using saves which might have saved 'mid-script' etc. Autosaves just happen when they please so they don't follow my rules [SHAKES FIST] so I don't use them. I know this is easier said than done with the amount of times this game crashes, so I'm not saying don't ever use them, just try to make your own saves more frequently... talking of which...)
6. Make plenty of Manual Saves and Quick Saves. (YES, I'M TALKING TO YOU [POINTS]. With any open world game, like Witcher 3, Skyrim, ACV, ACO etc there's a lot more going on in the background than say, something like Doom Eternal (this isn't an insult [pushes the Doom fans back into the cupboard] so it really doesn't make sense to keep using only one save. You might mess up that save in some way and then all you have to reply on is Auto saves (and this game can sometimes Autosave 5 times in a minute and a half) so do yourself (and your sanity) a favour and make a lot of saves. As an example I'll explain my save routine... get comfy... not that comfy though, doing it like that is bad for your back) I'll normally use Manual Saves before/after important situations such as before starting a new mission, finishing a mission. I'll make a save before a quest, then during that mission I'll use QuickSaves (like, before getting to the 'action' area (fort, camp etc) then if the quest moves on to somewhere else, I'll make a QS after finishing that part and then when I get close to the next 'action' areaI'll make another. I'll do that until I finish the mission. (I'm running out of words for mission and quest, can I borrow your thesaurus) This may sound tedious to some but if the game crashes I rarely have to replay more that a few minutes of gameplay to get back to where I was (excluding River Raids and 'Red' areas). I'm not saying you have to follow this to the letter only explaining how I do it. (Also F5 on the keyboard is QuickSave so it's not too laborious, think of it as a mini workout for fingers and brain lol))
7. If you think a bug has started in your game go back to a previous save ASAP... maybe. (Some bugs can become stuck in your save file in games so if something funky happens and reloading the game doesn't fix it then it might be worth a try to go back to a point before that bug appeared, and if you followed my advice above (or you make plenty of saves anyway) then this shouldn't be a problem [POINTS AGAIN].
8. Try not to have too many unfinished quests open at once (what I mean by this is don't start an arc in england, do a quest or two and then bugger of to france to do that DLC. The only reason I brought this up is because I think I've seen it mentioned maybe 3 times that this has caused an issue for some players so it might be worth considering).

I've always done most of the above (I started using these after having some painful times on a modded Skyrim) but the ones I've added to my routine lately (because of the frequent crashing) was number 1 and 2. I'm not saying these are a magic fix-all and yeah, it simply could have been patch 1.5.1 that fixed my crashing but some people are still having the frequent crashing on 1.5.1 and mine has stopped... so maybe something else is working, either way the things noted above are good things to use in any open world game (IMO).

@ubi-thrupney

Thanks for the reply and taking the time to read it .

I know this (number 1 and 2) could be a placebo effect but like I mentioned, I started using it for days before updating and it seemed to stop my crashing and is still working so far, (my only crash was last night and that was my first in over 30 hours (a simple crash that didn't happen again upon replay)).

What brought me to the idea of doing a number 2 (ahem) was how I would react when I'd crash, I'd load the game up as quick as possible, and 'press any key' and load my game up ASAP and they were the days I was crashing frequently.

So yeah, I'd be interested to know also if these tips help someone.

@simplethumb

1. It used to be that you could set up the Ubisoft app so it would shut down with the game but they broke that feature and it hasn't worked correctly in over a year and you have to shut it down manually so there could be some validity in that. That was always one of my major gripes with Steam, the damn thing is always running in the background and it is sending data back to Steam which I'm sure they are using for advertising reason
2. This too makes some sense because if you look in your Documents/Assassin's Creed Valhalla/ folder you'll find a folder that says cache and in it has some sort of data files that get cached when you quit the game and then read back when you start the game back up ... Mine has file dates going clear back to 10/5/2021 which was the date I reloaded the game and tried to play it again after deleting the game a couple of weeks after launch because it was so damned buggy (but before all the crashing issues which didn't start until December 2020) If I hadn't deleted the game there would likely have been files dating all the way back to the release date
3. and 4. This is interesting too because with Odyssey you made your quick saves when you were in the menu and why they changed it is beyond me but I think it has something to do with the way Ashraf Ismail liked to do things because Origins was even worse, you could not make any saves at all, all you had was one autosave to work with and if something went bad you had to completely start all over again. That poor save mechanism bit me a couple of times, first when the added the Animus Control Panel it broke the game for everyone with a Ryzen CPU and you'd get random crashes and I happened to have one fighting this big snake in a dream sequence and I couldn't get out of it, it would always crash before I could beat him and then send me right back into the start of that sequence so I was caught in a loop and I had no recourse other than starting all over again. Then in June 2021 I decided to record a full playthrough of Origins and about half way through the recording glitched and shut off and I played for about an hour before I realized it but there was no way to go back and replay and re-record the missing part because of that stupid save mechanism so I just quit because now it was pointless

As for Skyrim you should never use quick save, it's alway been broken and you should always make hard saves which don't have the problem you describe. In fact I use a mod that removes Quick Save from the menu altogether leaving only the hard save choice and several times I've put over 300 hours on a run without ever breaking my save file and I always run over 600 mods at a time and the game is infinitely more stable than Valhalla ... Ditto with Witcher 3 another game I mod the hell out of yet it remains stable as long as I do things properly. With Valhalla every other update seems to break the game and I have to spend hours trying to get it stable so I've pretty much given up on it. I did finally complete the main game last October but I got the Season Pass on sale around Thanksgiving and never even got to start it because it was crashing so much I just decided to hell with it and still haven't gotten motivated enough to try to stabilize the game again if that is even possible.

@longjohn119

Thanks for the write up

It seems that when they changed the Ubi launcher they broke a few things going by what some people were saying over on Reddit the other day

I have to restart the Ubi launcher if I crash because it has something funky in it which doesn't like VPN's (I have about 1 minute to start a game, because if I don't then a banner appears at the bottom of the launcher saying something like "while you continue playing we'll restore your connection that got interupted.." and at that point it won't let me start any game and that banner hangs around for a few minutes). Other people who've had this issue have tried the fixes Ubi mods have recommended and it didn't fix it. So, because of that, that is what got me started on reloading it. If there's the issue I've just mentioned and also the issues you mentioned then yeah, maybe there might be something to that.

On the topic of number 2 there's a mod that makes the game start a lot faster by removing the splash screens at the beginning (it was mentioned in another thread a week or 2 ago), and with the amount this game crashes for some people I can imagine a lot more users would want to install something like that. I used a similar mod on Dead Rising 2 recently (I think it was that game) and the mod author commented that he couldn't make the splash screen instant because then the game would crash (or fail to load) so he made them take a few seconds. So that is what lead me to the idea that maybe more time might be needed to load the basegame stuff, especially for people using that mod. Also, I only shutdown/restart my PC twice a week (all other times I Hibernate it) and as mentioned there'd be days were I'd crash constantly and days were it played fine for hours... so that was something else that lead me to number two's thinking, were the crashes more frequent on the days were I'd done a PC restart and then started the game too quickly (I was gonna include this explaination in my OP but it seemed too long already lol).

It's a shame you lost so much when ACOr crapped out, sounds like a double whammy . I really hate games with only Autosaves, (though I know some have it for 'mechanical' reasons) so although it's a little bit tedious I back up those autosaves in a different folder because I really hate having to redo the same things in games that I've already done so if I lost a Autosave (basically lost all progress) and I'd have to start from the beginning again as you did with your video playthrough, then yeah, that'd probably be enough for me to not wanna play a game again.

Talking about Skyrim, I think I remember hearing/reading what you mentioned about quick saves though I played it back in 2016 (and only had a measly 120ish mods lol). There was a rumour about not overwriting a save file, that it could bork up that save (because scraps of data could be left over from the old save) so you should delete that save then make a new one... it ended up being false and nothing to worry over... I've still kept that habit though with all games to this day lol.

@longjohn119 temporary solution in my PC, is i am always use Vsync=ON, limit fps into 90 only..... that is it......not so much CTD for now, it is better than using unlimited fps.....

@simplethumb Actually you don't need a mod to get rid of the starting videos, you can just delete them manually or do what I do and that is tack .bak on them. The reason I do that is they get replaced after every update or anytime you verify the files and with the .bak extension then I know which of the new files I need to delete without having to go look it up again. Same is true for Odyssey.

Yeah in Skyrim I make a new save every time and every once in a while I go in and delete the oldest ones because it doesn't take long before you have several GB of saves in that folder. Also if you are running SKSE it also makes a separate save of it's data each time so it can add up fast when you make a save every 10-15 minutes

@longjohn119

That's a good point about the .bak, easier to do too. Thanks

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