Image Quality and Overclockability
GA660 vrs. MSI AGPhantom
Here is where
the REAL differences bewteen these to cards come into play. Although
the installation and set up of both cards was very straight forward,
the outcome after we had them installed was markedly different.
Here's how we set things up.
Tower ATX Case w/ 300W PS, Pentium3
-450 Overclocked to 558 MHz. w/ a 124MHz. FSB and also clocked to
517MHz. with a 115MHz. FSB,
Abit BE6 Motherboard, 128MB PC133 HSDRAM from EMS, WD Expert
AC418000 7200 RPM ATA66 Hard Drive, MSI
3DAGPhantom 32MB AGP and Gigabyte GA660 Turbo 32MB AGP,
Toshiba SDM1202 3rd. Gen. 4.8X DVD/32X CDROM, Win 98, NVidia
Reference Drivers Version 2.08, DirectX 7.0
installed both boards with their included drivers just to get a feel
for the "out of the box" set up. We then set both boards
up with the latest NVidia reference drivers just to level the
playing field. We used Entech's
to overclock these cards as well as check their current clock
We installed the
AGPhantom in our test bed machine without a hitch. The card had no
problem handling the 124MHz. front Side Bus and the 82MHz. AGP Bus
that the Abit BE6 generates at that setting with a 2/3 divider. The
card was clocked at a standard 140MHz. Core and 155 Memory Clock. It
was perfectly stable at this setting. We
were also able to overclock the card up to 165 MHz. Core and 160
MHz. Memory clocks without one lock-up or visual artifact.
was surprised that the memory had such a limited margin but as soon
as we took it up past 160MHz., "snow" would occur in 3D
games. In general, this card was a stable and competent overclocker
and it handled the higher AGP bus speeds well.
One somewhat bothersome
issue was the Windows Desktop or 2D image quality. The
desktop image was noticably more fuzzy and less crisp in all areas
vrs. the GA660 Turbo. This was prevalent with both the stock MSI
drivers and the latest reference drivers, so it seems to be a
hardware issue. Those running 1024X768 desktops or smaller
resolutions, should not have a problem. It was only at 1152X768 or
above that the image became unstable.
GA660 Turbo was a "horse of a different color" all
together. Perhaps it is because of it Electric Blue FR4 Material
that they make the PCB out of but it goes a little further than
that. As you noted in the previous page, the GA660 Turbo comes with
two distinct features, the excellent FAN/Sink Combos on both front
and BACK sides of the board and the "Turbo Jumper" for the
Core and Memory clocks. This is where our fun began. For almost a
day and a half I was pulling my hair out on why the GA660 would lock
up in Quake2 and Quake3 but boot and run the Windows environment
without a hitch. We tried everything including running the card at
its standard 135/140 clocks without the Turbo Jumper. Everytime it
locked. Then light dawned on our marble heads and we set the FSB
clock on the Abit BE6 to 100MHz. which put our Pentium !!!
450 back to its specified speed. Like magic the GA660 ran all apps.
without fuss. This allowed the AGP bus on the motherboard to run
down at its specified 66MHz. clock. We then bumped up the FSB and
left the divider on the BE6 at 2/3. We
made it up to 115 MHz. FSB or 76 MHz. AGP bus speed without
lock-ups. If we took the GA660 any higher, it would lock. However,
we were able to run the board in "Tubo" Mode which allowed
for a 156MHz. Core and Memory Clock, once we set the FSB clock back
to 115 on the motherboard. Also,
the board would not handle a higher core or memory clocks higher
than "Turbo Mode" without locking up.
Here is a shot of the Gigabyte Clock Slider Drivers in action...
This was a
little dissapointing to say the least since we were so impressed by
the GA660's excellent cooling solution. I get the feeling the
thermal junction between the heat sink and TNT2 chip is not adequate
for the application. Finally,
the Desktop Image Quality for the GA660 Turbo was superb. It does a
great job at displaying crisp text and rich graphics like most TNT2
enough talk. Let's wire these puppies up, punch the button and watch