What is HPET?

[Lord_Karango17]

I just had to disable this to get war thunder to run at anything over 30 fps, so what exactly is its purpose, and what are the consequences of disabling it?

[Muz]

sauce :^)  http://forums.anandtech.com/showthread.php?t=2362109

[Lord_Karango17]

Screen Shot 2015-11-16 at 10.38.43 AM.png

sauce :^)  http://forums.anandtech.com/showthread.php?t=2362109

I see. It seems that disabling HPET isn't a very good idea, but with it on, war thunder is an unplayable piece of garbage...

 

For some reason the cpu usage is much higher with HPET on in war thunder, than with it off...

[Muz]

I see. It seems that disabling HPET isn't a very good idea, but with it on, war thunder is an unplayable piece of garbage...

 

For some reason the cpu usage is much higher with HPET on in war thunder, than with it off...

I have the exact same CPU but I have an R9 390 instead and the game runs fine? I'm not sure what's up with your 780ti.

[Lord_Karango17]

I have the exact same CPU but I have an R9 390 instead and the game runs fine? I'm not sure what's up with your 780ti.

Its a single core on the cpu being maxed out leading to awful framerates. Most of the time the gpu usage is sub 50% because of the fact.

[XDroidie626]

Its a single core on the cpu being maxed out leading to awful framerates. Most of the time the gpu usage is sub 50% because of the fact.

Game single core optimized? or even locked

[Lord_Karango17]

Game single core optimized? or even locked

The game is allowed to use all the cores but only uses teh 1st core on both my desktop, and laptop.

 

This was not a problem like a year ago, but its just go worse and worse, to a point where I spend most of a match running 30-40 fps, which looks piss when combined with my monitor.

[Muz]

Its a single core on the cpu being maxed out leading to awful framerates. Most of the time the gpu usage is sub 50% because of the fact.

Very odd indeed.

[Lord_Karango17]

The game is allowed to use all the cores but only uses the 1st core on both my desktop, and laptop.

 

This was not a problem like a year ago, but its just go worse and worse, to a point where I spend most of a match running 30-40 fps, which looks piss when combined with my monitor.

[BrightCandle]

The problem with HPET is that the motherboard has quite a lot to do with its implementation. There have been so many cases of motherboards with major performance problems around HPET. Sometimes it manifests itself as a high DPC but sometimes it doesn't. Usually the manufacturer will do something about it post release and the latest bios and drivers will repair the problem but often its just something they never address and you have little choice but to turn it off as programs that use it suffer severe problems. I wish the news was better but in the Z77 days there were a lot of problems with it, I had issues with HPET on my original Asus board for X79 but the Asrock had a working implementation from the outset.

[Lord_Karango17]

The problem with HPET is that the motherboard has quite a lot to do with its implementation. There have been so many cases of motherboards with major performance problems around HPET. Sometimes it manifests itself as a high DPC but sometimes it doesn't. Usually the manufacturer will do something about it post release and the latest bios and drivers will repair the problem but often its just something they never address and you have little choice but to turn it off as programs that use it suffer severe problems. I wish the news was better but in the Z77 days there were a lot of problems with it, I had issues with HPET on my original Asus board for X79 but the Asrock had a working implementation from the outset.

Unfortunately the newest bios for the sabertooth z77 is late 2013. So far nothing has wigged out because HPET is off, but I'm sure something I use often will be borked...

[BrightCandle]

Unfortunately the newest bios for the sabertooth z77 is late 2013. So far nothing has wigged out because HPET is off, but I'm sure something I use often will be borked...

 

Nothing catastrophic is going to happen if you have it off. There are certain calls in the Windows API that rely on it and allow programmers to get very detailed timing information and set jobs precisely in the future which aren't as precise with it off but most games are designed to work with both possibilities as is all software. You aren't going to notice much difference with it off.

 

I would as a programmer I might be doing some benchmarking of a routine and using the high precision timers and find my resolution was now ~10ms because I didn't have the HPET turned on and hence would need to loop my algorithm a lot to get some accuracy. There is the potential that a game using a frame lock around 60hz might stutter more because the resolution of the timer its using is much worse, but whether you'll even notice or not is unlikely. Besides having a poorly performing HPET which has major DPC issues isn't good for that same game either.