You have a hyperthreading capable CPU which means windows sees it as 2 seperate processors. Since dosbox is singlethreaded it can use only 1 (virtual) cpu at the time.

I see. So 50% is maximum for DOSBox. Too bad.

Thank you very much.

No 50% is the maximum for any single threaded app. Your actually running 100% on a single virtual processor but Windows shows it as 50% because it see's 2 "processors" it's not a DosBox limitation.

You'll probably get better performance disabling hyperthreading and trying DosBox. Dunno since I never got into the Intel Hyperthreading Hype.

Anonymous wrote:

I see. So 50% is maximum for DOSBox. Too bad.
Thank you very much.

This is nonsense value based on Windows assumption that you have two processors. In 2 processor system you would be using 50%, but in your case you are using 100% (since you have one processor).
Hyperthreading is just a way how to improve multitasking, the added processor is just virtual (you will not get the perfomance of 2 processor system - you still have only one processor).

Mirek

I would disable HT in bios to see what happens. If you are not satisfied, you can always enable it again. To me, this HT thing seems suspicially bogus. 😈

Once I had to optimize a raytracer application by using multiple threads and I was quite astonished that HT brought about 15% performance increase (compared to a version without any threading constructs).

Yeah, that's about all you can expect from HT. The general idea is that a CPU consists of many parts (several integer math units, floating point math, mmx, sse, ...) and a single program/thread usually can't keep all units busy, so they added hardware support for "simultaneous" execution of two threads in order to keep more units of the CPU busy. But they didn't actually add any more CPU units, so if two threads want to do (for example) floating-point math, one of them has to wait, just like without HT. Nice idea, but not worth more than a few percent performance.

Anyway, 10-15% percent performance increase is better than nothing.

Ah but is 10-15% performance for certain applications on an Intel Processor with HyperThreading better than just owning an AMD processor? 😉

Not to mention actually having 2 cores 😉