Well, when running R4V2, I would hit this problem and I would just chalk it up to the apic issue. So I just upgraded. Now, the first time I select 'Watch TV', everything goes great. The second time, it freezes after a few seconds, and In the mythbackend log I get:

Couldn't read data from the capture card in 15 seconds. Game over, man.

I am running myth on a shuttle SV25 ( North bridge:VIA Twister-T PN133T
South bridge:VIA 686B), with a 733Mhz PIII, 128Mb RAM, PVR250 (the OEM model w/o remote) WD 160 Hard drive, home-made lirc receiver, and lite-on DVD-ROM. Specs for the modo are below here:
http://us.shuttle.com/specs2.asp?pro_id=377

Here's dmesg from the box:
root@challenger:~ # dmesg
Linux version 2.4.25-chw (root@km_dev.mysettopbox.tv) (gcc version 3.3.2 20030812 (Debian prerelease)) #1 Sat Apr 10 15:46:31 PDT 2004
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 00000000000a0000 (usable)
BIOS-e820: 00000000000f0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 0000000006ff0000 (usable)
BIOS-e820: 0000000006ff0000 - 0000000006ff3000 (ACPI NVS)
BIOS-e820: 0000000006ff3000 - 0000000007000000 (ACPI data)
BIOS-e820: 00000000ffff0000 - 0000000100000000 (reserved)
0MB HIGHMEM available.
111MB LOWMEM available.
On node 0 totalpages: 28656
zone(0): 4096 pages.
zone(1): 24560 pages.
zone(2): 0 pages.
Kernel command line: auto BOOT_IMAGE=Linux ro root=301 hda=scsi hdb=scsi hdc=scsi hdd=scsi hde=scsi hdf=scsi hdg=scsi hdh=scsi apm=power-off nomce
ide_setup: hda=scsi
ide_setup: hdb=scsi
ide_setup: hdc=scsi
ide_setup: hdd=scsi
ide_setup: hde=scsi
ide_setup: hdf=scsi
ide_setup: hdg=scsi
ide_setup: hdh=scsi
Initializing CPU#0
Detected 731.271 MHz processor.
Console: colour VGA+ 80x25
Calibrating delay loop... 1458.17 BogoMIPS
Memory: 110484k/114624k available (1363k kernel code, 3756k reserved, 490k data, 116k init, 0k highmem)
Dentry cache hash table entries: 16384 (order: 5, 131072 bytes)
Inode cache hash table entries: 8192 (order: 4, 65536 bytes)
Mount cache hash table entries: 512 (order: 0, 4096 bytes)
Buffer cache hash table entries: 4096 (order: 2, 16384 bytes)
Page-cache hash table entries: 32768 (order: 5, 131072 bytes)
CPU: L1 I cache: 16K, L1 D cache: 16K
CPU: L2 cache: 256K
CPU serial number disabled.
CPU: After generic, caps: 0383f9ff 00000000 00000000 00000000
CPU: Common caps: 0383f9ff 00000000 00000000 00000000
CPU: Intel Pentium III (Coppermine) stepping 03
Enabling fast FPU save and restore... done.
Enabling unmasked SIMD FPU exception support... done.
Checking 'hlt' instruction... OK.
POSIX conformance testing by UNIFIX
mtrr: v1.40 (20010327) Richard Gooch (rgooch@atnf.csiro.au)
mtrr: detected mtrr type: Intel
PCI: PCI BIOS revision 2.10 entry at 0xfb500, last bus=1
PCI: Using configuration type 1
PCI: Probing PCI hardware
PCI: Probing PCI hardware (bus 00)
PCI: Using IRQ router VIA [1106/0686] at 00:07.0
isapnp: Scanning for PnP cards...
isapnp: No Plug & Play device found
Linux NET4.0 for Linux 2.4
Based upon Swansea University Computer Society NET3.039
Initializing RT netlink socket
Starting kswapd
VFS: Disk quotas vdquot_6.5.1
Detected PS/2 Mouse Port.
pty: 256 Unix98 ptys configured
floppy0: no floppy controllers found
RAMDISK driver initialized: 16 RAM disks of 4096K size 1024 blocksize
loop: loaded (max 8 devices)
Uniform Multi-Platform E-IDE driver Revision: 7.00beta4-2.4
ide: Assuming 33MHz system bus speed for PIO modes; override with idebus=xx
VP_IDE: IDE controller at PCI slot 00:07.1
VP_IDE: chipset revision 6
VP_IDE: not 100% native mode: will probe irqs later
VP_IDE: VIA vt82c686b (rev 40) IDE UDMA100 controller on pci00:07.1
ide0: BM-DMA at 0xd000-0xd007, BIOS settings: hda:DMA, hdb:pio
ide1: BM-DMA at 0xd008-0xd00f, BIOS settings: hdc:DMA, hdd:pio
hda: WDC WD1200JB-75FUA0, ATA DISK drive
hdc: JLMS XJ-HD166S, ATAPI CD/DVD-ROM drive
ide0 at 0x1f0-0x1f7,0x3f6 on irq 14
ide1 at 0x170-0x177,0x376 on irq 15
hda: attached ide-disk driver.
hda: host protected area => 1
hda: 234375000 sectors (120000 MB) w/8192KiB Cache, CHS=14589/255/63
ide-cd: passing drive hdc to ide-scsi emulation.
hdc: attached ide-scsi driver.
Partition check:
hda: hda1 hda2 hda3 hda4
ide: late registration of driver.
Promise Fasttrak(tm) Softwareraid driver 0.03beta: No raid array found
Highpoint HPT370 Softwareraid driver for linux version 0.02
Guestimating sector 234355964 for superblock
driver for Silicon Image(tm) Medley(tm) hardware version 0.0.1: No raid array found
SCSI subsystem driver Revision: 1.00
scsi0 : SCSI host adapter emulation for IDE ATAPI devices
Vendor: JLMS Model: XJ-HD166S Rev: DS18
Type: CD-ROM ANSI SCSI revision: 02
Attached scsi CD-ROM sr0 at scsi0, channel 0, id 0, lun 0
sr0: scsi3-mmc drive: 48x/48x cd/rw xa/form2 cdda tray
Uniform CD-ROM driver Revision: 3.12
Initializing Cryptographic API
NET4: Linux TCP/IP 1.0 for NET4.0
IP Protocols: ICMP, UDP, TCP, IGMP
IP: routing cache hash table of 512 buckets, 4Kbytes
TCP: Hash tables configured (established 8192 bind 16384)
NET4: Unix domain sockets 1.0/SMP for Linux NET4.0.
RAMDISK: Compressed image found at block 0
Freeing initrd memory: 149k freed
VFS: Mounted root (ext2 filesystem).
Journalled Block Device driver loaded
kjournald starting. Commit interval 5 seconds
EXT3 FS 2.4-0.9.19, 19 August 2002 on ide0(3,1), internal journal
EXT3-fs: mounted filesystem with ordered data mode.
Freeing unused kernel memory: 116k freed
Adding Swap: 1108476k swap-space (priority -1)
EXT3 FS 2.4-0.9.19, 19 August 2002 on ide0(3,1), internal journal
Real Time Clock Driver v1.10f
usb.c: registered new driver usbdevfs
usb.c: registered new driver hub
usb-uhci.c: $Revision: 1.275 $ time 16:10:01 Apr 10 2004
usb-uhci.c: High bandwidth mode enabled
PCI: Found IRQ 11 for device 00:07.2
PCI: Sharing IRQ 11 with 00:07.3
PCI: Sharing IRQ 11 with 00:0c.0
usb-uhci.c: USB UHCI at I/O 0xd400, IRQ 11
usb-uhci.c: Detected 2 ports
usb.c: new USB bus registered, assigned bus number 1
hub.c: USB hub found
hub.c: 2 ports detected
PCI: Found IRQ 11 for device 00:07.3
PCI: Sharing IRQ 11 with 00:07.2
PCI: Sharing IRQ 11 with 00:0c.0
usb-uhci.c: USB UHCI at I/O 0xd800, IRQ 11
usb-uhci.c: Detected 2 ports
usb.c: new USB bus registered, assigned bus number 2
hub.c: USB hub found
hub.c: 2 ports detected
usb-uhci.c: v1.275:USB Universal Host Controller Interface driver
Serial driver version 5.05c (2001-07-08) with MANY_PORTS SHARE_IRQ SERIAL_PCI ISAPNP enabled
ttyS00 at 0x03f8 (irq = 4) is a 16550A
parport0: PC-style at 0x378 [PCSPP,EPP]
parport_pc: Via 686A parallel port: io=0x378
8139too Fast Ethernet driver 0.9.26
PCI: Found IRQ 11 for device 00:0c.0
PCI: Sharing IRQ 11 with 00:07.2
PCI: Sharing IRQ 11 with 00:07.3
eth0: RealTek RTL8139 at 0xc78f5000, 00:30:1b:ac:93:10, IRQ 11
eth0: Identified 8139 chip type 'RTL-8100B/8139D'
Linux agpgart interface v0.99 (c) Jeff Hartmann
agpgart: Maximum main memory to use for agp memory: 77M
agpgart: Unsupported Via chipset (device id: 0605), you might want to try agp_try_unsupported=1.
agpgart: no supported devices found.
PCI: Found IRQ 3 for device 00:07.5
PCI: Sharing IRQ 3 with 00:0b.0
PCI: Setting latency timer of device 00:07.5 to 64
ttyS1: LSR safety check engaged!
ttyS1: LSR safety check engaged!
kjournald starting. Commit interval 5 seconds
EXT3 FS 2.4-0.9.19, 19 August 2002 on ide0(3,4), internal journal
EXT3-fs: mounted filesystem with ordered data mode.
eth0: link up, 100Mbps, full-duplex, lpa 0x45E1
eth0: link up, 100Mbps, full-duplex, lpa 0x45E1
blk: queue c0316080, I/O limit 4095Mb (mask 0xffffffff)
lirc_dev: IR Remote Control driver registered, at major 61
lirc_serial: auto-detected active low receiver
lirc_dev: lirc_register_plugin:sample_rate: 0
Linux video capture interface: v1.00
i2c-core.o: i2c core module version 2.6.1 (20010830)
i2c-algo-bit.o: i2c bit algorithm module
i2c-core.o: driver i2c TV tuner driver registered.
i2c-core.o: driver saa7115 registered.
i2c-core.o: driver i2c msp3400 driver registered.
ivtv: version 0.1.9 (release) loading
ivtv: SGarray_size = 340, DSGarray_size = 16
ivtv: Found an iTVC15 based chip
PCI: Found IRQ 12 for device 00:0a.0
ivtv: Unreasonably low latency timer, setting to 64 (was 32)
tuner: chip found @ 0xc2
i2c-core.o: client [(tuner unset)] registered to adapter [ivtv i2c driver #0](pos. 0).
tuner: type forced to -1 (<NULL>) [insmod]
tuner: type set to 2 (Philips NTSC (FI1236,FM1236 and compatibles))
saa7114.c: starting probe for adapter ivtv i2c driver #0 (0x10005)
saa7114.c: detecting saa7114 client on address 0x42
saa7115.c: writing init values
status: (1E) 0x89, (1F) 0xb1
i2c-core.o: client [saa7115[0]] registered to adapter [ivtv i2c driver #0](pos. 1).
msp34xx: init: chip=MSP3448W-A2, has NICAM support
msp3410: daemon started
i2c-core.o: client [MSP3448W-A2] registered to adapter [ivtv i2c driver #0](pos. 2).
i2c-core.o: adapter ivtv i2c driver #0 registered as adapter 0.
ivtv: Encoder revision: 0x02040011
ivtv: Decoder revision: 0x02020023
ivtv: Registered v4l2 device, minor 0
ivtv: Registered v4l2 device, minor 32
ivtv: Registered v4l2 device, minor 224
ivtv: loaded
bttv: driver version 0.9.12 loaded
bttv: using 8 buffers with 2080k (520 pages) each for capture
i2c-core.o: driver i2c ir driver registered.
saa7115[0]: decoder set norm NTSC
saa7115[0] set audio: 0x02
saa7115[0]: decoder set input (0)
saa7115[0]: now setting Composite input
saa7115[0]: decoder set size
Setting full NTSC width
Setting full NTSC height
saa7115[0]: decoder set input (4)
saa7115[0]: now setting Composite input
saa7115[0]: decoder set norm NTSC
saa7115[0] set audio: 0x02
saa7115[0]: decoder set picture bright=128 contrast=63 saturation=64 hue=0
saa7115[0]: decoder set picture bright=128 contrast=63 saturation=63 hue=0
saa7115[0]: decoder set picture bright=127 contrast=63 saturation=63 hue=0
saa7115[0]: decoder set picture bright=127 contrast=63 saturation=63 hue=0
apm: BIOS version 1.2 Flags 0x07 (Driver version 1.16)
saa7115[0]: decoder set norm NTSC
saa7115[0] set audio: 0x02
saa7115[0]: decoder set picture bright=127 contrast=63 saturation=63 hue=0
saa7115[0]: decoder set picture bright=127 contrast=63 saturation=63 hue=0
saa7115[0]: decoder set picture bright=127 contrast=63 saturation=63 hue=0
saa7115[0]: decoder set picture bright=127 contrast=63 saturation=63 hue=0
saa7115[0]: decoder set size
Hpsc: 0x00001, Hfsc: 0x00600
Setting full NTSC height
saa7115[0]: decoder disable output
saa7115[0]: decoder enable output
spurious 8259A interrupt: IRQ7.
root@challenger:~ #

Dude the apic issue is with nforce motherboards. The problem with via motherboards is a dma bug and there is no known solution, other than getting a different motherboard.

Considering that this seems to crop up quite often, and so far I have not heard of a solution from VIA, I just checked google for anything similar, perhaps 'via dma throughput', and see that Toms hardware spotted a issue a couple of years back where the VIA chipset was recognizing that the drive had the capability, but wasn't passing the data at the expected throughput. One of their testing solutions was to drop a Promis UltraDMA66 board in the motherboard. Testing after that showed a significant improvement through that board, over the motherboard connector.

I am going to see if doing that provides a workaround for this issue. If not I will be doing a motherboard and version upgrade, as I am getting kind of tired of discovering that MythBackEnd has died overnight and I have lost a days worth of recordings.

If necessary I will pull one of my video capture cards. I have enough spare parts around to add it to a different system and try to make that into a slave recorder. (Haven't had much luck with that via knoppmyth so far, keeps wanting to be a front end box. If someone has handy instructions, I would appreciate a post in the how-to forums for that side of the setup.)

-Rusty

_________________
Master:
- AMD 1800XP on a MSI KT4V motherboard, via KT400 bios
- 120 G Segate Baracuda /, /cache, /myth, swap
- 200 G Segate Baracuda /myth/tv
- 3 Haupauge! WinTV PVR250s
- 19" Daewoo Monitor (1280x1024 ni)

having had my share of anoyances with myth-backend freezing, and with the notes above, I stopped into my local MicroCenter today and picked up a SIIG UltraATA 100 PCI card to see if using it would resolve the via dma issues.

I don't consider what I have done so far to be a great test of it, but I am a bit happier with it than my previous experience provided.

I have been doing transcoding of Dilbert episodes to get them onto SVCDs. At the same time I have been recording two tv shows, watching one of them delayed, and have watched several shows while two other shows were being recorded.

I don't thnk MythBackend has run as long as a week without having to be restarted for me on this system. Two days seems to be about the maximum. I figure if it runs for over a month without having to be restarted, that this is a reasonable alternative for people who already have a VIA motherboard.

Cost was $29.95 plus tax. I could have gotten a Promise card online for less, but it would have had to wait a couple of days. Instalation was basically a snap, but it does mean that for the moment I am down one slot fan.

-Rusty

_________________
Master:
- AMD 1800XP on a MSI KT4V motherboard, via KT400 bios
- 120 G Segate Baracuda /, /cache, /myth, swap
- 200 G Segate Baracuda /myth/tv
- 3 Haupauge! WinTV PVR250s
- 19" Daewoo Monitor (1280x1024 ni)