Hyperthreading - ? for PC Hardware Gurus

[Werewolf]

WTF!!!

When I replaced my PC about a year ago I bought into the Intel Hyperthreading hype hook line and sinker. It was gonna be almost as good as having two real CPU's...

Turns out that may not be so - at least not for PC's used primarily for gaming. I've had HT enabled since I bought the PC. Didn't have any real problems running the numerous installed games except for Civ 4 which reboot at random times. Well the Firaxis guys fixed that problem - there are 100's of thousands of players of that game and the designers couldn't ignore the complaints.

Not so with Dangerous Waters (a Naval Simulation by an outfit called Sonalysts). A number of folks have complained about HT causing instability, including me and have been ignored. Finally I just gave up and turned HT off at the BIOS level and that cured my problems with DW.

I was a bit pissed though at the thought of giving up performance right up until I realized I hadn't. Everything still runs just as fast or faster. Off the top of my head Civ 4, Sims 2 and Falcon 4 Allied Force all run better. The other stuff is at least as fast and none that I have noticed run slower.

So what the heck is the deal with Hyperthreading? What's the point? Even a google search pretty much reveals that only a very, very limited number of apps that do special tasks are impacted.

Is Hyperthreading just more marketing hype designed to sucker in guys like me into paying that extra few bucks for a feature that really does nothing?

[TarpleyG]

Is Hyperthreading just more marketing hype designed to sucker in guys like me into paying that extra few bucks for a feature that really does nothing?

Yep.  A processor can only handle so many requests and can only handle them so fast.  Not much else you can squeeze out of them.

Greg

[Gewehr98]

I dunno.

I'm happy with the machines in this house, which are either IBM or Dell dual-Xeon workstations and servers.

While only so many software titles are multi-threaded, the nice thing about multiple-CPU computers is that they offer quite a bit of headroom when the load gets heavy, even for single-threaded apps.  Since I switched to multiple CPU machines, I've run WinNT Workstation, Win2K, and now XP Pro, and have noticed that if one CPU gets dragged down executing an application, other threads are automatically shuffled off to the second CPU for execution. Linux is good with multiple-CPU machines, too, as I'm dabbling with it.

This can be rather nice, depending on how much multitasking one is trying to accomplish.  Playing a non-multithreaded hardcore computer game on a dual-CPU machine allows the game to completely take 100% out of one CPU, so the operating system simply shuffles itself and other ancillary threads over to the second CPU. If the game's multi-threaded, that's even better, it'll get one CPU plus whatever percent of the second CPU the operating system deems is safe to allocate.

Something my wife and stepson does is Adobe Creative Suite work, and burning huge .pdf files to CD-ROM for shipment to the big offset printers of a small real estate book we assist.  Adobe Photoshop is multithreaded, and firing up Roxio CD Creator at the same time causes nary a hiccup.  Part of the job requires we print ad copy proofs for both the realtor and offset printer QC using myTektronix Phaser 780 color laser, and anybody who prints big high-resolution color .pdf files knows that can tie things up.  The Phaser has an internal hard drive and lots of memory, but it still burns CPU cycles formatting the .pdf for transmission over the Cat 5 network cable to the printer.  The dual-CPU Xeons seem to take this all in stride.    

Since I retired, I'm playing with a quad-CPU machine in my evil lab, ostensibly to assist with the real estate book editing and production, but more for my learning curve, as it is running Windows Server 2003 and Linux.  It should be fun...

[Fatcat]

I dunno, I saw some improvements with HT. Rendering in 3ds is definately affected, about 15% faster than with HT off. Multitasking in general is improved. I wouldn't call it completely a shill, but it certainly isn't as good as they played it out to be.

I have heard about problems with games & HT, but I've never seen them myself. Are all your motherboard/chipset drivers up to date? You have the 1.03 patch for dangerous waters?

A little off topic, but I realized the other day this P4 has lasted me the longest of any processor I have had. The fact that it pulls an almost 1 GHz overclock (on air no less) certainly helps. It'll be replaced by an Athlon X2 box this summer, but it sure had a good run.

[Werewolf]

GeWehr you pretty much validate my research. From what I can find the only app that really benefits from HT is adobe photoshop.

Fatcat, I do have the 1.03 patch for DW and the only way I can get custom missions I creat to run without random reboots is to turn off HT at the BIOS level. Prior to that I was getting reboots with the canned missions and could cure that by setting DW's affinity to just a single CPU. What a pain.

I've got an ASUS MB P800 something or other deluxe. ASUS made them about 2 to 3 years ago and no longer does. As near as I can tell all the chipset drivers are up to date at least there aren't any newer on the ASUS site than the one's I've got.

DW has a problem with HT pure and simple. I'm not the only one having problems. But Sonalyst will not acknowledge it and the DW forums at sonalyst pretty much shout down, flame, ignore or otherwise ostracize anyone who has the audacity to criticize DW.

OH WELL... It's a good game anyway.