Isochronous support в биосе что

SPEC CPU2006 and CPU2017 Flag Description — Platform settings for New H3C systems

cpupower frequency-set cpupower utility is a collection of tools for power efficiency of processor. frequency-set sub-command controls settings for processor frequency. «-g [governor]» specifies a policy to select processor frequency. The performance governor statically sets frequency of the processor cores specified by «-c» option to the highest possible for maximum performance. nohz_full This kernel option sets adaptive tick mode (NOHZ_FULL) to specified processors. Since the number of interrupts is reduced to ones per second, latency-sensitive applications can take advantage of it.

Firmware / BIOS / Microcode Settings

Enhanced Halt State (C1E) Enabling this option which is the default allows the processor to transmit to its minimum frequency when entering the power state C1. If the switch is disabled the CPU stays at its maximum frequency in C1. Because of the increase of power consumption users should only select this option after performing application benchmarking to verify improved performance in their environment. The default is «Enabled». DCU Streamer Prefetcher This BIOS switch allows 2 options: «Enabled» and «Disabled». The default is «Enabled». This prefetcher is a L1 data cache prefetcher, which detects multiple loads from the same cache line done within a time limit, in order to then prefetch the next line from the L2 cache or the main memory into the L1 cache based on the assumption that the next cache line will also be needed. Hardware Prefetch The hardware prefetcher operates transparently, without programmer intervention, to fetch streams of data and instruction from memory into the unified second-level cache. The prefetcher is capable of handling multiple streams in either the forward or backward direction. It is triggered when successive cache misses occur in the last-level cache and a stride in the access pattern is detected, such as in the case of loop iterations that access array elements. The prefetching occurs up to a page boundary. This feature can be disabled through the BIOS. Default is Enable. Enforce POR This can be one of the following: [Disable] or [Enable]. Enable to enforce POR (Plan Of Record) restriction for DDR4 frequency and voltage programming. Memory speeds will be capped accordingly. Disabling allows user selection of additional supported memory speeds. Isoc Mode Enabling the isochronous (ISOC) mode option reduces the credits available for memory traffic. For memory requests, this option reduces latency at the expense of throughput under heavy loads. Select Enable to enable Isochronous support to meet QoS (Quality of Service) requirements. This feature is especially important for Virtualization Technology. Adjacent Cache Prefetch The Adjacent Cache-Line Prefetch mechanism, like automatic hardware prefetch, operates without programmer intervention. When enabled through the BIOS, two 64-byte cache lines are fetched into a 128-byte sector, regardless of whether the additional cache line has been requested or not. In applications with relatively poor spatial locality, the cache miss ratio is higher. A cache miss on an Intel Pentium 4 processor-based system (with adjacent sector prefetch enabled) brings in 128 byte, leading to higher bus utilization (assuming that the application did not need the other 64 bytes). When adjacent sector prefetch is disabled, an Intel Pentium4 processor-based system only fetches 64 bytes. The other 64 bytes of the sector in the last-level cache are not used unless the application explicitly issues a load to that address. Disabling adjacent sector prefetch on Intel Pentium4 processor-based systems can reduce bus traffic. Default is Enable. Hardware P-States This BIOS switch allows 4 options: «Native Mode», «Disabled», «Out of Band Mode» and «Native Mode with No legacy Support». The default is «Native Mode». With Hardware Power Management(HWPM) the processors provides a flexible interface between Hardware and Platform for performance management and improving energy efficiency. In Native Mode the HWPM operates cooperatively with the OS via a software interface to provide constraints and hints. When disabled, system does not use HWPM. EIST PSD Function Function of the Enhanced Intel SpeedStep Technology (EIST). EIST reduces the latency inherent with changing the voltage-frequency pair (P-state), thus allowing those transitions to occur more frequently. This allows for more granular, demand-based switching and can optimize the power-to-performance balance, based on the demands of the applications. Power Supply Mode (Default = Balanced Performance) This BIOS switch allows 4 options: «Balanced performance», «Performance», «Balanced Energy» and «Energy Efficient». The default is «Balanced Performance» optimized to maximum power savings with minimal impact on performance. «Performance» disables all power management options with any impact on performance. «Balanced Energy» is optimized for power efficiency and «Energy Efficient» for power savings. The BIOS switch is only selectable if the BIOS switch «Power Technology» is set to «Custom». The two options «Balanced Performance» and «Balanced Energy» should always be the first choice as both options optimize the efficiency of the system. In cases where the performance is not sufficient or the power consumption is too high the two options «Performance» or «Energy Efficient» could be an alternative. IMC Interleaving This BIOS option controls the interleaving between the Integrated Memory Controllers (IMCs). There are two IMCs per socket in Skylake Server. If IMC Interleaving is set to 2-way, addresses will be interleaved between the two IMCs. If IMC Interleaving is set to 1-way, there will be no interleaving. If SNC is disabled, IMC Interleaving should be set to 2-way. If SNC is enabled, IMC Interleaving should be set to 1-way. This BIOS switch allows 3 options: «Auto» , «1-way Interleave» and «2-way Interleave». Default setting is «Auto». Hyper-Threading [all] This BIOS option enables or disables additional hardware thread which shares same physical core. Generally «Enabled» is recommended but disabling it makes sense for the application which requires the shortest possible response times. Default setting is «Enabled». Link Frequency Select This switch allows the configuration of the Intel Ultra Path Interconnect (UPI) link speed. Default is auto, which configures the optimal link speed automatically. It can be set «9.6 GT/s», «10.4 GT/s» or «Auto». LLC dead line alloc This BIOS switch allows 2 options: «Enabled» and «Disabled». The default is «Enabled». In the Skylake non-inclusive cache scheme, the mid-level cache (MLC) evictions are filled into the last-level cache (LLC). When lines are evicted from the MLC, the core can flag them as «dead» (i.e., not likely to be read again). The LLC has the option to drop dead lines and not fill them in the LLC. If the Dead Line LLC Alloc feature is disabled, dead lines will always be dropped and will never fill into the LLC. This can help save space in the LLC and prevent the LLC from evicting useful data. However, if the Dead Line LLC Alloc feature is enabled, the LLC can opportunistically fill dead lines into the LLC if there is free space available. Package C State This BIOS option allows 6 options: «C0/C1», «C2», «C6(non Retention)», «C6(Retention)», «No Limit» and «Auto». The default setting is «Auto». Package C-states is one of energy-saving options of the processor, which not only allow the individual cores of a processor, but the entire processor chip to be put into a type of sleep state. As a result, power consumption is even further reduced. But the «waking-up time» that is required to change from the lower package C-states to the active (C0) state is even longer in comparison with the CPU or core C-states. If the «C0» setting is made in the BIOS, the processor chip always remains active. It can improve the performance of latency sensitive workloads. Patrol Scrub This BIOS option enables or disables the so-called memory scrubbing, which cyclically accesses the main memory of the system in the background regardless of the operating system in order to detect and correct memory errors in a preventive way. The time of this memory test cannot be influenced and can under certain circumstances result in losses in performance. The disabling of the Patrol Scrub option increases the probability of discovering memory errors in case of active accesses by the operating system. Until these errors are correctable, the ECC technology of the memory modules ensures that the system continues to run in a stable way. However, too many correctable memory errors increase the risk of discovering non-correctable errors, which then result in a system standstill. Stale AtoS This BIOS switch allows 2 options: «Enabled» and «Disabled». The default is «Disabled». The in-memory directory has three states: I, A, and S. I (invalid) state means the data is clean and does not exist in any other socket’s cache. A (snoopAll) state means the data may exist in another socket in exclusive or modified state. S (Shared) state means the data is clean and may be shared across one or more socket’s caches. When doing a read to memory, if the directory line is in the A state we must snoop all the other sockets because another socket may have the line in modified state. If this is the case, the snoop will return the modified data. However, it may be the case that a line is read in A state and all the snoops come back a miss. This can happen if another socket read the line earlier and then silently dropped it from its cache without modifying it. If Stale AtoS feature is enabled, in the situation where a line in A state returns only snoop misses, the line will transition to S state. That way, subsequent reads to the line will encounter it in S state and not have to snoop, saving latency and snoop bandwidth. Stale AtoS may be beneficial in a workload where there are many cross-socket reads. Sub NUMA Cluster Sub NUMA Cluster (SNC) breaks up the last-level cache (LLC) into two disjoint clusters based on address range, with each cluster bound to one memory controller. SNC improves average latency to the LLC/memory and is a replacement for the «Cluster On Die» (COD) feature found in previous processor families. For a multi-socketed system, all SNC clusters are mapped to unique NUMA domains. IMC Interleaving must be set to the correct value to correspond with SNC enable/disable. If SNC and IMC Interleave are both set to Auto, the result will be SNC disabled (only one cluster per socket) with 2-way IMC interleave. If SNC is set to Enable, IMC Interleave should be set to 1-way, which will result in two clusters per socket. The BIOS switch «Sub NUMA Clustering» allows 3 options: «Auto», «Enabled» and «Disabled». The default setting is «Disabled». Intel VT for Directed I/O (VT-d) This BIOS option enables or disables I/O virtualization functions of the CPU. If the server is not used for virtualization, this option should be set to «Disabled». Default setting is «Enabled». VMX This BIOS option enables or disables additional virtualization functions of the CPU. If the server is not used for virtualization, this option should be set to «Disabled». This can result in energy savings. Default setting is «Enabled». Trusted Execution Technology Enable Intel Trusted Execution Technology (Intel TXT). The default setting is «Disabled». XPT Prefetcher This option configures the processor Xtended Prediciton Table (XPT) prefetch feature. The XPT prefetcher exists on top of other prefetchers that that can prefetch data in the core DCU, MLC, and LLC. The XPT prefetcher will issue a speculative DRAM read request in parallel to an LLC lookup. This prefetch bypasses the LLC, saving latency. In some cases, setting this option to disabled can improve performance. In some cases, setting this option to disabled can improve performance. Typically, setting this option to enable provides better performance. This option must be enabled when Sub-NUMA Clustering is enabled. Values for this BIOS option can be: Enabled: Allows a read request sent to the LLC to speculatively issue a copy of the read to the memory controller requesting the prefetch. Disabled: Does not allow the LLC to speculatively issue copies of reads. Disabling this will also disables Sub-NUMA Cluster (SNC). DCA DCA(Direct Cache Access) capable I/O devices such as network controllers can place data directly into the CPU cache, which improves response time. Enabling this option allows processors to increase I/O performance by placing data from I/O devices directly into the processor cache. This setting helps to reduce cache misses. The default setting is «Disabled». Workload Configuration Controls the aggressiveness of the energy performance BIAS settings. This bit field allows the Basic Input-Output System (BIOS) to choose a configuration that may improve performance on certain workloads. Can be UMA or NUMA. The default is «UMA». Autonomous Core C-State This BIOS switch allows 2 options: «Enabled» and «Disabled». The default is «Disabled». Enabled: HALT and C1 request get converted to C6 requests in hardware. Disabled: only C0 and C1 are used by the OS. C1 gets enabled automatically when an OS autohalts.

TR Forums

Last Christmas, I tried to build a PC for my parents (you can see the thread about it here). It almost worked properly, except that any 2D graphics (e.g. YouTube) caused a hard crash within a random time interval between 15 seconds and 3 minutes. I went through at least half a dozen ATI drivers, tried hacking the profiles to stop the clocks from going down to save power, etc. etc. — none of it was any use. I had tested the RAM, the temperatures and everything else I could think of and all indicated that it should work fine, so I assumed the video card was simply broken, but since they didn’t care that much, I left it be (mainly because I was out of time).

This year, when returned for vacation, I ordered an Nvidia card to replace the ATI one. but even that did not help. The behavior of the crash changed (it simply froze instead of going to a monochromatic display and then freezing), but the fact that it inevitably crashed within minutes did not. I was at my wits end and looking through the BIOS to get rid of Turbo Boost and lower the RAM speeds when under miscellaneous, I saw a setting called «Isochronous Support» which was enabled. I Googled it and all I could find was that it has something to do with the interaction between the northbridge and southbridge. For lack of anything better to try, I disabled it and my mother has been peacefully watching YouTube for the past 2.5 hours.

The motherboard is the Gigabyte GA-P55-UD3R from last year’s Utility Player. Does anyone know what this thrice accursed «Isochronous Support» is and why it is on by default?

Darth Gerbil
Posts: 7728 Joined: Sat Apr 24, 2004 7:53 pm Location: the abyss into which you gaze

Re: «Isochronous Support» and GPU problems

Wed Dec 22, 2010 1:06 am

Isochronus refers to time-bound processes, such as synchronizing audio and video in a multimedia stream or ensuring that data is transferred across a network or data bus (like a northbridge or southbridge on a motherboard) with similar constraints. If the feature isn’t working on your mobo and shutting it off doesn’t cause any additional problems, maybe it’s broken on your copy. Shutting it off is as good a fix as any, though I’d be interested to hear what Gigabyte had to say about it. Is the board still under warranty?

Gigabyte GA-X58-USB3 Review

If you are reading this review, then most likely you know exactly what the BIOS of your motherboard is used for; however, if you don’t, then you are going to want to read this section pretty carefully as it does explain what each screen you may encounter is and what it does to your system. There are two main reasons for going into the BIOS, the first is to setup your computer to make sure you have your hard drives booting in the order you wish. The other main reason that someone may find themselves in the BIOS is to overclock their computer, as overclocking through the BIOS will give you the most stable overclock as opposed to overclocking through the operating system.

The first screen when navigating the BIOS is the BIOS Main Screen. From here you are going to be able to navigate to the other screens where you can change any of the settings you may want to. At the bottom of the main screen is a list of functions that you can do such as press Esc to quit, F8 to enter Q-Flash, arrow keys to move around, F10 to save and exit, F11 to save CMOS to BIOS, and F12 to load CMOS to BIOS. The first menu that I want to take a look at is the MB Intelligent Tweaker (M.I.T.). This screen is where you are going to go to begin overclocking your system. When you go in this screen, you are going to see more sub menus, as well as some current status of your system at the bottom of the screen such as your BIOS Version, the current BCLK, CPU Frequency, Memory Frequency, Total Memory Size, CPU Temperature, Vcore and DRAM Voltages. To see more detailed current status you are going to enter the first submenu called M.I.T. Current Status. When you select into the Advanced Frequency Settings menu, you are going to see the first section of where you are going to tweak settings to overclock different aspects of your system.

The first value that you can change is your CPU Clock Ratio (if it is unlocked, you are going to be able to raise it but if not you can only lower the multiplier). You are going to get a pop up when you press enter with the value selected, this is where you are going to be able to key in what value you wish to set, you can see it gives you 12 as a minimum and 21 as a maximum. There is a submenu here that you can go into called Advanced CPU Core Features, this is where you are going to enable or disable Intel Turbo Boost Tech, you are also going to be able to enable all four cores of the processor or select which core you wish to use if you only want one enabled. You can turn off the CPU Multi-Threading technology here as well if you wish to. CPU Enhanced Halt (C1E) is a seating that helps with saving power by lowering the CPU clock speed and voltages during the system halt state to help save power. C3/C6/C7 State Support is another power saving features that once again lowers your CPU clock and voltage settings when different system halt states are active to once again save power, but this feature is more advanced than C1E. CPU Thermal Monitor is the setting that you are going to either enable or disable that will monitor the CPU temperature and when the CPU is overheating, the CPU clock speeds and voltages will be reduced to protect the chip. CPU EIST Function is a setting that is going to control the Intel SpeedStep feature, which is going to lower your CPU clock speeds and voltages during lower CPU usage to reduce not only power but heat production. The final setting on this page is the BI-Directional PROCHOT; when this setting is enabled the CPU or chipset will be able to detect that overheating is occurring and will send a signal will be sent to lower the CPU performance to decrease heat production. If the setting is disabled, that will only allow the CPU to detect whether an overheating is occurring. Press the ESC button to back out of this submenu and get back to the Advanced Frequency Settings page. You are also going to be able to change your QPI Clock Ratio. The options are Auto, x36, x44, x48, and Slow Mode as your choices. When you choose which one you want, the QPI Link Speed will automatically update on this screen to let you know what your new selection will adjust it to. The Uncore Clock Ratio is the next setting you are going to be able to change. Your choices are from between Auto and x12 to x48. You are going to want to keep your Uncore Frequency around 2x of your memory speeds. The Base Clock, or BCLK as many people refer to it, is where you are going to get into the fun part of overclocking. This multiplied by your multiplier is going to specify your CPU Frequency (ex. 133 x 20 = 2.66 GHz). You are going to be able to change the BCLK anywhere from 100MHz and 600MHz.

The System Memory Multiplier is the setting that you are going to change to get your memory speeds. The options are Auto, 6x, 8x, 10x, 12x, 14x, 16x, and 18x. The Advanced Clock Control is for more seasoned overclockers and enables achievement of a stable overclock when you are looking to gain every last single MHz. The first setting is the CPU Clock Drive. This setting allows adjustment of the amplitude of the CPU and Chipset Clock. The settings available are 700mV, 800mV, 900mV, and 1000mV with 800mV being the default setting. The PCI Express Clock Drive allows the user to set the amplitude of the PCI Express and Chipset clock, with the same options as the CPU Clock Drive (however, 900mV being the default setting). You can set the CPU Clock Skew towards the bottom, which allows you to set the CPU clock prior to the Chipset clock. The IOH Clock Skew allows the user to set the North Bridge clock prior to the CPU clock. Both of these settings have values between 0ps and 750ps, in multiples of 50ps with a default of 0ps.

You can overclock your memory or set your memory settings by goiing back to the MIT screen and selecting the Advanced Memory Settings menu. The first option is the Extreme Memory Profile — this is an option you may choose to use to have the factory default timings and other settings loaded for you based on what kind of memory you have installed in your system. If it is set to disabled, you set the settings manually. The System Memory Multiplier on this screen again, even though you can set it under the Advanced Frequency Settings screen. As you can see, the options are all the same as the previous screen. The next setting on this screen is the Performance enhance. There are three options here: Standard, which lets the system operate at its basic performance level; Turbo, which lets the system operate at good performance level; Extreme, which lets the system operate at its best performance level. The DRAM timing Selectable setting enables the user to adjust the memory settings at three levels: Auto, Quick, or Expert. Auto will lock the manual adjustments to be made, Quick will allow your basic memory timings, and Expert will unlock all of your timings to be changed. You can clock into Channel A/B/C Timing settings, which are where you are going to be able to adjust all of your RAM timings and the Channel A/B/C Turnaround settings, which provide access to the Turnaround settings.

By selecting the Advanced voltage Settings from the MIT screen, a screen appears that allows you to change all of the different voltage settings of your system. Default values for all settings on this page are Auto; directly to the left of all of the changeable values are what the default settings are. The first setting on this page is the Load-Line Calibration. This setting allows the user to compensate for the vdroop. The second setting is your CPU Vcore. This is your CPU core voltage. Dynamic Vcore is only adjustable when your CPU Vcore is set to normal and allows you to add a little bit of Vcore to your stock CPU Vcore. You are going to get QPI/VTT, CPU PLL, PCIE, QPI LL, IOH Core, ICH I/O, ICH Core, DRAM Voltage, DRAM Termination, CH-A/B/C Data VRef, and CH-A/B/C Address VRef settings that you can control. Back on the Main MIT screen, the final menu is the Miscellaneous Settings. Here you only have two settings that can be changed — Isochronous Support and Virtualization Technology. Isochronous Support will be able to determine whether to enable specific streams within the CPU and chipset. The default setting is Enabled, with the only other option as disabled. Virtualization Technology will enable to disable Intel Virtualization Technology, which will allow a system to run multiple operating systems and applications in independent platforms.

The standard CMOS Features screen allows the user to change the date and time, as well as view the different hard drives and optical drives which may be installed. You are also going to see the Halt On option here. This setting is going to allow you to determine if the system will stop for any errors, no errors, or all errors except for a keyboard error. If you click into a hard drive you have installed in your system to manually set it, you are going to get the IDE Channel Slave option as well as the Access Mode settings. You will also see the Capacity of the drive as well as some other features of the drive listed such as the Cylinder, Head, Precomp, Landing Zone, and Sector. The advanced BIOS Features is where you are going to be able to set the Hard Disk Boot Priority, as well as the First, Second, and Third Boot Devices. On this screen you can enable or disable the Quick Boot feature, or set the Password Check. You can also change the HDD SMART Capabilities, limit CPUID Max to 3, No-Execute Memory Protect, Delay for HDD (in seconds), Full Screen Logo Show, Backup BIOS Image to HDD, as well as set which video card is going to get your Initial Display if you have more than one card installed.

The integrated Peripherals screen is where you are going to be able to enable or disable different features of the motherboard. The Extreme Hard Drive setting is going to enable or disable function of the SATA controllers integrated in the Intel ICH10R chipset. ICH SATA Control Mode is where RAID selection in the BIOS can be dealt with. Other devices to enable or disable are the USB controllers on the board as well as the LAN controller. Clicking into the SMART LAN submenu shows the status of a LAN cable attached to the motherboard. Under the Power Management Setup menu, users can set different power functions such as how the computer is turned on — Power on by Mouse or Keyboard, which would allow the computer to be turned on by a random keyboard button press or mouse click. The PC Health Status screen displays the current Vcore, DRAM voltages, +3.3V, +5V and +12V status of your power supply, System Temperature, CPU Temperature, and MCH temperature. Your CPU Fans, System Fan2, Power Fan, and System Fan1 speeds are going to be listed on this page as well. You can also set your CPU Warning temperature.

Back on the Main BIOS screen, on the right hand side of the screen you are going to have listed your Load Fail-Safe Defaults, Load Optimized Defaults, Set Supervisor Password, Set User Password, Save & Exit Setup, and Exit without saving. Any one of these menus will pop up with a red popup asking you for an input if you wish to carry out the command you are attempting to select. For the passwords, you will get a text input box where you can set the password that you may want installed on the motherboard. The Supervisor password is what is going to be required to go into the BIOS and the User password will need to be typed in before the system can pass the POST screen.

Now that we know what the BIOS looks like and where all the settings are located, it’s time to get to our testing setup, lineup of different benchmarks, and overclocking.